Topic 8 · Inside the atom — the scripts

What you are deciding: go-ahead for video generation on this topic, card by card.

Out of scope: articles and PP100 items (not on this page).

Here: the intro video, 5 lesson videos (3 marked by the author as “could do without a video”) and the summary video, in teaching order. Each card: the script, the attached question, then the quiz the student meets after the video.

How: tap one button per card. Taps and notes save as you go and are sent; the Notes tab shows what has gone and re-sends.

Intro video · teaches nothing, opens the question110 words · about 0:55

Introduction: Inside the atom

Script
SayScreen
Here is a pencil mark, and the dark stuff in it is carbon.[a pencil draws a mark]
Close up, the mark is a box of gray circles: the carbon atoms.[a zoom circle: a box of gray circles]
One of those circles is the smallest piece that is still carbon.[one gray circle lifted out]
Yet scientists can take an atom apart and look at what is inside.[the circle opens; what is inside stays blurred and unlabeled]
And here are two atoms that look almost the same, yet one is carbon and one is nitrogen.[two atom drawings side by side]
So what is inside an atom, and what decides which element it is?[the opened circle; question mark]
To find out, we will look inside the atom, and at what makes one element different from another.[the opened circle stays]
Okay, so are you ready to look inside an atom?[the three replies appear]

The ready line's poll — the attached item (no key; the intro teaches nothing)

video

Okay, so are you ready to look inside an atom?

  1. A Yes, let's go! — Great. Here we go.
  2. B Not sure yet — That's fine. We take it one particle at a time.
  3. C Let me watch that again — Good idea. Watch it again, then come back.
Answer

No key. A poll: every reply is accepted with its friendly line.

Your note · the intro video
What to judge

Is this content better than the current alternative students have (PhysicsGraph / Edmentum)?

8/10 on:

  • Clear and concise language
  • Physics accuracy (read as chemistry accuracy here; his line as pasted for HS Physics)
  • No "clangers" (content that causes a problematic misconception)
  • Appropriate questions
  • Initial testing
  • Expansion into harder questions (no exam)
  • The tasks should use similar language to that of the lesson

Gut check: better than the alternative? Would a student benefit? Full criteria

Lesson 1 of 5Author: could do without a video185 words · about 1:32

Three kinds of particle inside every atom

MAT-049 · Atoms contain three kinds of subatomic particle — Name the three subatomic particles found in every atom.

Script
SayScreen
A pencil leaves a dark mark on paper, and the dark stuff in the mark is carbon.[a pencil draws a mark; label CARBON]
Carbon is an element, so every atom in the mark is a carbon atom.[a zoom circle opens: a box of gray circles]
One carbon atom is the smallest piece that is still carbon, yet scientists can take an atom apart. What is inside?[one gray circle lifted out; question mark]
Let's zoom in on one gray circle and open it up.[zoom lines; the circle becomes a large pale disc that fills the frame]
Inside it are much smaller particles, of three kinds.[the cluster and the dots appear inside the disc]
The filled circles marked plus are called protons.[chip: PROTON, pointer to a filled circle]
The open circles with no mark are called neutrons.[chip: NEUTRON, pointer to an open circle]
The small dark dots marked minus are called electrons.[chip: ELECTRON, pointer to a dot]
None of the three kinds is carbon; carbon is what the whole atom is.[the whole disc outlined, label CARBON ATOM]
Now consider an atom of helium. It holds the same three kinds, with fewer of each.[the helium atom beside the carbon atom; 2, 2, 2 against 6, 6, 6]
So, every atom contains three kinds of smaller particle: protons, neutrons and electrons.[the rule slide: the carbon atom and the helium atom, opened; chips PROTON, NEUTRON, ELECTRON; nothing else printed]
An atom of carbon and an atom of helium contain the same three kinds; only the numbers differ.[the two atoms with their counts]
So if you take one carbon atom from the pencil mark apart, you find those three kinds, not smaller pieces of carbon.[the mark, the one circle, the opened circle]
Okay, now your turn.[closing screen: one line — "Every atom contains three kinds of smaller particle: protons, neutrons and electrons."]

“Okay, now your turn.” — the attached question

video

A carbon atom from a pencil mark is opened up. What is inside it?

  1. A three kinds of smaller particle
  2. B smaller and smaller pieces of carbon
  3. C nothing at all: an atom is empty
Answer

Key: A — three kinds of smaller particle

Every atom contains three kinds of smaller particle.
They are protons, neutrons and electrons.
None of them is carbon.

Feedback per option

  • A Inside are protons, neutrons and electrons: three kinds of smaller particle.
  • B None of the three kinds is carbon; carbon is what the whole atom is.
  • C The opened-up atom holds particles: protons, neutrons and electrons.

Quiz after the video — the mastery check, 10 items

Q1recall

Cut a piece of nickel smaller and smaller, in your mind. What is the smallest piece that is still nickel?

  1. A one nickel atom
  2. B the smallest speck you can see
  3. C there is no smallest piece
Answer

Key: A — one nickel atom

Nickel is made of nickel atoms.
One nickel atom is still nickel, and anything smaller is not.
So one nickel atom is the smallest piece that is still nickel.

Feedback per option

  • A One nickel atom is the smallest piece that is still nickel.
  • B A speck you can see holds a huge number of nickel atoms.
  • C Nickel stops at the atom: one atom is the smallest piece.
Q2term

In this atom, what are the filled circles marked + called?

++−−

Typed answer

Answer

Accepted: protons · proton · the protons · a proton

The filled circles marked plus are called protons.
This atom has 2 protons, packed in the middle.
Q3term

In this atom, what are the open circles with no mark called?

+++++−−−−−

Typed answer

Answer

Accepted: neutrons · neutron · the neutrons · a neutron

The open circles with no mark are called neutrons.
This atom has 6 neutrons, packed in the middle with the protons.
Q4term

In this atom, what are the small dark dots marked − called?

+++++++++−−−−−−−−−

Typed answer

Answer

Accepted: electrons · electron · the electrons · an electron

The small dark dots marked minus are called electrons.
This atom has 9 electrons, on the rings around the middle.
Q5what

Does an atom of iron contain neutrons?

  1. A yes
  2. B no
Answer

Key: A — yes

Every atom is built from protons, neutrons and electrons.
An iron atom's nucleus holds neutrons packed in with its protons.
So an iron atom contains neutrons.

Feedback per option

  • A An iron atom's nucleus holds protons and neutrons packed together, so it contains neutrons.
  • B An iron atom's nucleus holds neutrons packed in with its protons.
Q6what

Does an atom of sulfur contain protons, neutrons and electrons?

  1. A yes
  2. B no
Answer

Key: A — yes

Every atom contains protons, neutrons and electrons.
A sulfur atom is an atom.
So a sulfur atom contains all three kinds.

Feedback per option

  • A Every atom contains all three kinds, sulfur included.
  • B Sulfur atoms are atoms, and every atom contains all three kinds.
Q7what

Do only the atoms of metals contain protons?

  1. A yes
  2. B no
Answer

Key: B — no

Every atom contains protons, neutrons and electrons.
Oxygen and helium are not metals, and their atoms are atoms.
So their atoms contain protons too: not only the atoms of metals.

Feedback per option

  • A Every atom contains protons, metal or not: oxygen atoms and helium atoms have them too.
  • B Every atom contains protons; oxygen and helium are not metals, and their atoms have protons too.
Q8what

Which of these is NOT one of the three kinds of particle inside an atom?

  1. A a proton
  2. B a molecule
  3. C an electron
Answer

Key: B — a molecule

The three kinds of particle inside an atom are protons, neutrons and electrons.
A molecule is two or more atoms joined together.
So a molecule is not inside an atom; it is made of atoms.

Feedback per option

  • A A proton is one of the three kinds, drawn as a filled circle marked plus.
  • B A molecule is two or more whole atoms joined; it is made of atoms, so it cannot be inside one.
  • C An electron is one of the three kinds, drawn as a small dark dot marked minus.
Q9misconception

Iris says: "Take a gold atom apart, and inside you find tiny pieces of gold." Is Iris correct?

  1. A yes
  2. B no
Answer

Key: B — no

One gold atom is the smallest piece that is still gold.
Inside it are protons, neutrons and electrons, the same three kinds as in every atom.
None of those is gold, so Iris is not correct.

Feedback per option

  • A Taking an atom apart does not give smaller gold. Inside are protons, neutrons and electrons, and none of them is gold.
  • B Inside a gold atom are protons, neutrons and electrons. None of them is gold; gold is what the whole atom is.
Q10transfer

A scientist takes apart an atom of neon and an atom of iron. Which statement is correct?

  1. A The two atoms contain the same three kinds of particle.
  2. B Only the iron atom contains protons in its nucleus.
  3. C The neon atom contains a fourth kind of particle as well.
Answer

Key: A — The two atoms contain the same three kinds of particle.

Every atom contains three kinds of smaller particle: protons, neutrons and electrons.
A neon atom and an iron atom are both atoms.
So both contain the same three kinds, and only the numbers differ.

Feedback per option

  • A Every atom contains protons, neutrons and electrons; neon and iron differ only in the numbers.
  • B Every atom contains protons, the neon atom included.
  • C Every atom contains the same three kinds; there is no fourth kind in neon.
Your note · lesson 1: Three kinds of particle inside every atom
What to judge

Is this content better than the current alternative students have (PhysicsGraph / Edmentum)?

8/10 on:

  • Clear and concise language
  • Physics accuracy (read as chemistry accuracy here; his line as pasted for HS Physics)
  • No "clangers" (content that causes a problematic misconception)
  • Appropriate questions
  • Initial testing
  • Expansion into harder questions (no exam)
  • The tasks should use similar language to that of the lesson

Gut check: better than the alternative? Would a student benefit? Full criteria

Lesson 2 of 5Author: definitely a video198 words · about 1:39

Where each particle sits, and its charge

MAT-050 · Charge and location of each subatomic particle — State the charge and location of protons, neutrons, and electrons in an atom.

Script
SayScreen
Here is the inside of a lithium atom, a soft, silvery metal.[the lithium drawing builds: rings, then the cluster, then the dots]
Some particles sit packed in the middle.[the middle highlighted]
Others sit out on the rings.[the rings highlighted]
Some carry a plus mark, some a minus mark, and some no mark. Which particle sits where?[the marks flash; question mark]
In the middle, the protons and the neutrons sit packed together.[the cluster grows: 3 filled, 4 open]
This tiny packed center of the atom is called the nucleus.[a dashed ring round the cluster; chip: NUCLEUS]
The electrons sit on the rings, outside the nucleus.[the 3 dots appear on the rings; label ELECTRONS, OUTSIDE]
Now consider a wool sweater pulled off over your head. Your hair stands on end, because rubbing gave the hair a charge.[a sweater comes off; hair stands up; chip: CHARGE]
Charge comes in two kinds, positive and negative, and one of each cancels the other.[a + and a − slide together and fade]
So what do the marks mean?[the marks flash again]
Each proton carries a positive charge: that is its plus mark.[a proton enlarged, its + glows]
Each electron carries a negative charge.[a dot with its −]
A neutron carries no charge at all.[an open circle with nothing]
The drawing is a model: the real atom is mostly empty space, and electrons do not run on tracks.[the rings fade to faint; label MODEL]
So, protons and neutrons sit together in a tiny center called the nucleus.[the rule slide: the labeled lithium atom; chip NUCLEUS; nothing else printed]
Protons carry a positive charge; neutrons carry no charge.[a proton's plus glows; an open circle with nothing]
Electrons move around the outside of the nucleus and carry a negative charge.[the dots on the rings, minus marks glowing]
Okay, now your turn.[closing screen: bullets — • Protons and neutrons sit together in the nucleus • Protons: positive charge; neutrons: no charge • Electrons: negative charge, outside the nucleus]

“Okay, now your turn.” — the attached question

video

In a drawing of a lithium atom, the protons and neutrons sit packed together in the middle. What is that packed middle called?

  1. A the electron
  2. B the charge
  3. C the nucleus
Answer

Key: C — the nucleus

Protons and neutrons sit packed together in the middle of the atom.
That tiny packed center is called the nucleus.
The electrons move around the outside of it.

Feedback per option

  • A An electron is one of the dots on the rings, outside the middle.
  • B A charge is what a proton or an electron carries, not a place in the atom.
  • C The tiny packed center, holding the protons and neutrons, is called the nucleus.

Quiz after the video — the mastery check, 12 items

Q1recall

Which of these is one of the three kinds of particle found inside every atom?

  1. A a molecule
  2. B a neutron
  3. C an element
Answer

Key: B — a neutron

Every atom contains three kinds of smaller particle: protons, neutrons and electrons.
A neutron is one of the three.
A molecule and an element are made of atoms, not found inside one.

Feedback per option

  • A A molecule is two or more atoms joined; it is not inside an atom.
  • B Every atom contains protons, neutrons and electrons.
  • C An element is a substance made of one kind of atom; it is not a particle inside an atom.
Q2term

The tiny packed center of an atom, where the protons and neutrons sit, is called the…

Typed answer

Answer

Accepted: nucleus · the nucleus · a nucleus

The tiny packed center of an atom is called the nucleus.
Every proton and every neutron in the atom sits in it.
Q3term

What is the nucleus of an atom?

  1. A the packed middle, holding protons and neutrons
  2. B the outer ring that the electrons move around on
  3. C the whole atom, its particles and its empty space
Answer

Key: A — the packed middle, holding protons and neutrons

Protons and neutrons sit packed together in a tiny center.
That tiny packed center is called the nucleus.
The electrons move around the outside of it.

Feedback per option

  • A The nucleus is the tiny packed center where the protons and neutrons sit.
  • B The electrons move around the outside of the nucleus; the ring is not the nucleus.
  • C The nucleus is only the tiny packed center, not the whole atom.
Q4fluency

Which charge does a proton carry?

  1. A positive
  2. B negative
  3. C none
Answer

Key: A — positive

Each proton is drawn with a plus mark.
The plus mark means a positive charge.
So a proton carries a positive charge.

Feedback per option

  • A A proton carries a positive charge: that is what its plus mark means.
  • B An electron carries the negative charge; a proton carries a positive charge.
  • C A neutron carries no charge; a proton carries a positive charge.
Q5fluency

Where in an atom do the neutrons sit?

  1. A in the nucleus
  2. B on the rings, outside the nucleus
Answer

Key: A — in the nucleus

Protons and neutrons sit packed together in the tiny center.
That center is the nucleus.
So the neutrons sit in the nucleus.

Feedback per option

  • A Protons and neutrons sit packed together in the nucleus.
  • B The electrons sit on the rings; the neutrons sit in the nucleus with the protons.
Q6fluency

Which charge does an electron carry?

  1. A positive
  2. B negative
  3. C none
Answer

Key: B — negative

Each electron is drawn with a minus mark.
The minus mark means a negative charge.
So an electron carries a negative charge.

Feedback per option

  • A A proton carries the positive charge; an electron carries a negative charge.
  • B An electron carries a negative charge: that is what its minus mark means.
  • C A neutron carries no charge; an electron carries a negative charge.
Q7fluency

Where in an atom do the protons sit?

  1. A in the nucleus
  2. B on the rings, outside the nucleus
Answer

Key: A — in the nucleus

Protons and neutrons sit packed together in the tiny center.
That center is the nucleus.
So the protons sit in the nucleus.

Feedback per option

  • A Protons sit packed in the nucleus with the neutrons.
  • B The electrons sit on the rings; the protons sit in the nucleus.
Q8fluency

Which charge does a neutron carry?

  1. A positive
  2. B negative
  3. C none
Answer

Key: C — none

A neutron is drawn as an open circle with no mark.
No mark means no charge.
So a neutron carries no charge.

Feedback per option

  • A A proton carries the positive charge; a neutron carries none.
  • B An electron carries the negative charge; a neutron carries none.
  • C A neutron carries no charge at all: that is why it has no mark.
Q9fluency

Where in an atom do the electrons sit?

  1. A in the nucleus
  2. B on the rings, outside the nucleus
Answer

Key: B — on the rings, outside the nucleus

Electrons move around the outside of the nucleus.
The drawing puts them on the rings.
So the electrons sit on the rings, outside the nucleus.

Feedback per option

  • A Only protons and neutrons sit in the nucleus; the electrons sit outside it.
  • B The electrons sit on the rings, around the outside of the nucleus.
Q10fluency

Filled circles marked + are protons, open circles are neutrons, small dark dots marked − are electrons. Which kind of particle in this drawing sits outside the packed middle?

++−−
  1. A the electrons
  2. B the neutrons
  3. C the protons
Answer

Key: A — the electrons

The packed middle is the nucleus, and it holds the filled circles and the open circles: protons and neutrons.
The small dark dots sit out on the ring.
Small dark dots are electrons, so the electrons sit outside the nucleus.

Feedback per option

  • A The two small dark dots sit out on the ring: electrons, outside the nucleus.
  • B The two open circles sit in the packed middle: neutrons, in the nucleus.
  • C The two filled circles marked plus sit in the packed middle: protons, in the nucleus.
Q11fluency

Filled circles marked + are protons, open circles are neutrons, small dark dots marked − are electrons. Which kinds of particle in this drawing sit inside the packed middle?

+++++++++−−−−−−−−−
  1. A protons and electrons
  2. B electrons only
  3. C protons and neutrons
Answer

Key: C — protons and neutrons

The packed middle is the nucleus.
It holds filled circles marked plus and open circles: protons and neutrons.
The small dark dots, the electrons, sit on the rings outside it.

Feedback per option

  • A The small dark dots, the electrons, sit out on the rings, not in the middle.
  • B The dots on the rings are the electrons; the packed middle holds protons and neutrons.
  • C The packed middle holds the filled circles marked plus and the open circles: protons and neutrons.
Q12misconception

Elodie says: "The electrons sit in the nucleus, packed in with the protons." Is Elodie correct?

  1. A yes
  2. B no
Answer

Key: B — no

The nucleus is the packed center that holds the protons and the neutrons.
The electrons move around the outside of the nucleus, never inside it.
So Elodie is not correct.

Feedback per option

  • A The nucleus is packed, but only with protons and neutrons. The electrons move around the outside of it.
  • B Only protons and neutrons sit in the nucleus. The electrons move around the outside of it.
Your note · lesson 2: Where each particle sits, and its charge
What to judge

Is this content better than the current alternative students have (PhysicsGraph / Edmentum)?

8/10 on:

  • Clear and concise language
  • Physics accuracy (read as chemistry accuracy here; his line as pasted for HS Physics)
  • No "clangers" (content that causes a problematic misconception)
  • Appropriate questions
  • Initial testing
  • Expansion into harder questions (no exam)
  • The tasks should use similar language to that of the lesson

Gut check: better than the alternative? Would a student benefit? Full criteria

Lesson 3 of 5Author: could do without a video185 words · about 1:32

The proton count names the element

MAT-051 · The number of protons identifies the element — State which element an atom is given its number of protons.

Script
SayScreen
Here are two atoms drawn side by side, and they look almost the same.[the two atoms, unlabeled, side by side]
The left atom is carbon, the soot on a burnt match.[a burnt match; label CARBON under the left atom]
The right atom is nitrogen, the gas that makes up most of the air.[the sky; label NITROGEN under the right atom]
So what inside them tells them apart?[question mark between the atoms]
The number of protons does.[the protons in both atoms glow]
Count the protons in the left atom: 6 protons. Every atom with 6 protons is a carbon atom.[the six protons counted off; label CARBON]
Count the protons in the right atom: 7 protons. Every atom with 7 protons is a nitrogen atom.[the seven protons counted off; label NITROGEN]
Only the protons were counted; the neutrons were not.[chips: 6 PROTONS carbon / 7 PROTONS nitrogen; the neutrons dimmed]
Here are the first ten elements, from 1 proton to 10 protons.[the ten-row table slides in: proton count beside element name]
Find the count in the table and read off the element: 8 protons is oxygen.[row 8 highlighted]
And 4 protons is beryllium, 9 protons is fluorine, 2 protons is helium.[rows 4, 9 and 2 highlighted in turn; the three atoms with their names]
So, the number of protons decides which element an atom is.[the rule slide: the two atoms and the table; nothing else printed]
Count the protons, find that number in the table, and read off the element.[a finger traces row 7 across]
So in the two atoms, 6 protons make carbon and 7 protons make nitrogen; the proton count tells them apart.[the two atoms, labeled]
Okay, now your turn.[closing screen: one line — "The number of protons decides which element an atom is."]

“Okay, now your turn.” — the attached question

video

Two atoms look almost the same, but one is carbon and one is nitrogen. What tells them apart?

  1. A the number of protons
  2. B the number of neutrons
  3. C the size of the drawing
Answer

Key: A — the number of protons

The number of protons decides which element an atom is.
A carbon atom has 6 protons.
A nitrogen atom has 7 protons.

Feedback per option

  • A The number of protons decides which element an atom is: 6 protons is carbon, 7 protons is nitrogen.
  • B The neutrons do not decide the element.
  • C The two drawings are the same size; the proton count tells them apart.

Quiz after the video — the mastery check, 13 items

Q1recall

In which part of an atom do the protons sit?

  1. A in the nucleus
  2. B on the rings, outside the nucleus
Answer

Key: A — in the nucleus

Protons and neutrons sit packed together in the tiny center of the atom.
That center is the nucleus.
So the protons sit in the nucleus.

Feedback per option

  • A Protons and neutrons sit packed together in the nucleus.
  • B The electrons sit on the rings; the protons sit in the nucleus.
Q2fluency

Filled circles marked + are protons, open circles are neutrons, small dark dots marked − are electrons. The table gives the first ten elements and their proton counts. Count the protons: which element is this atom?

++−−elementprotonshydrogen1helium2lithium3beryllium4boron5carbon6nitrogen7oxygen8fluorine9neon10

Typed answer

Answer

Accepted: helium

Count the filled circles marked plus: 2 protons.
Find 2 in the table: helium.
So the atom is helium.
Q3fluency

The table gives the first ten elements and their proton counts. Under it is one atom's proton count: which element is that atom?

elementprotonshydrogen1helium2lithium3beryllium4boron5carbon6nitrogen7oxygen8fluorine9neon10this atom: 5 protons
  1. A boron
  2. B carbon
  3. C beryllium
Answer

Key: A — boron

The atom has 5 protons.
Find 5 in the table: boron.
So the atom is boron.

Feedback per option

  • A 5 protons: the table says boron.
  • B Carbon has 6 protons; this atom has 5.
  • C Beryllium has 4 protons; this atom has 5.
Q4fluency

Filled circles marked + are protons, open circles are neutrons, small dark dots marked − are electrons. The table gives the first ten elements and their proton counts. Count the protons: which element is this atom?

++++++++−−−−−−−−elementprotonshydrogen1helium2lithium3beryllium4boron5carbon6nitrogen7oxygen8fluorine9neon10

Typed answer

Answer

Accepted: oxygen

Count the filled circles marked plus: 8 protons.
Find 8 in the table: oxygen.
So the atom is oxygen.
Q5fluency

The table gives the first ten elements and their proton counts. Under it is one atom's proton count: which element is that atom?

elementprotonshydrogen1helium2lithium3beryllium4boron5carbon6nitrogen7oxygen8fluorine9neon10this atom: 10 protons

Typed answer

Answer

Accepted: neon

The atom has 10 protons.
Find 10 in the table: neon.
So the atom is neon.
Q6fluency

Filled circles marked + are protons, open circles are neutrons, small dark dots marked − are electrons. The table gives the first ten elements and their proton counts. Count the protons: which element is this atom?

+++−−−elementprotonshydrogen1helium2lithium3beryllium4boron5carbon6nitrogen7oxygen8fluorine9neon10
  1. A helium
  2. B beryllium
  3. C lithium
Answer

Key: C — lithium

Count only the filled circles marked plus: 3 protons.
The 4 open circles are neutrons, and they do not decide the element.
Find 3 in the table: lithium.

Feedback per option

  • A Helium has 2 protons; this atom has 3 filled circles marked plus.
  • B Beryllium has 4 protons; this atom has 3 filled circles marked plus. The open circles are neutrons, and they do not decide the element.
  • C 3 protons: the table says lithium.
Q7fluency

The table gives the first ten elements and their proton counts. Under it is one atom's proton count: which element is that atom?

elementprotonshydrogen1helium2lithium3beryllium4boron5carbon6nitrogen7oxygen8fluorine9neon10this atom: 7 protons

Typed answer

Answer

Accepted: nitrogen

The atom has 7 protons.
Find 7 in the table: nitrogen.
So the atom is nitrogen.
Q8fluency

Filled circles marked + are protons, open circles are neutrons, small dark dots marked − are electrons. The table gives the first ten elements and their proton counts. Count the protons: which element is this atom?

+++++++++−−−−−−−−−elementprotonshydrogen1helium2lithium3beryllium4boron5carbon6nitrogen7oxygen8fluorine9neon10
  1. A oxygen
  2. B fluorine
  3. C neon
Answer

Key: B — fluorine

Count only the filled circles marked plus: 9 protons.
The 10 open circles are neutrons, and they do not decide the element.
Find 9 in the table: fluorine.

Feedback per option

  • A Oxygen has 8 protons; this atom has 9 filled circles marked plus.
  • B 9 protons: the table says fluorine.
  • C Neon has 10 protons; this atom has 9 filled circles marked plus. The open circles are neutrons and do not decide the element.
Q9fluency

Filled circles marked + are protons, open circles are neutrons, small dark dots marked − are electrons. The table gives the first ten elements and their proton counts. Count the protons: which element is this atom?

++++−−−−elementprotonshydrogen1helium2lithium3beryllium4boron5carbon6nitrogen7oxygen8fluorine9neon10
  1. A boron
  2. B beryllium
  3. C lithium
Answer

Key: B — beryllium

Count only the filled circles marked plus: 4 protons.
The 5 open circles are neutrons, and they do not decide the element.
Find 4 in the table: beryllium.

Feedback per option

  • A Boron has 5 protons; this atom has 4 filled circles marked plus. The open circles are neutrons and do not decide the element.
  • B 4 protons: the table says beryllium.
  • C Lithium has 3 protons; this atom has 4 filled circles marked plus.
Q10fluency

The table gives the first ten elements and their proton counts. How many protons does every atom of oxygen have?

elementprotonshydrogen1helium2lithium3beryllium4boron5carbon6nitrogen7oxygen8fluorine9neon10an atom of oxygen

Typed answer

Answer

Accepted: 8 · 8 protons · eight

Find oxygen in the table.
The table says 8.
So every oxygen atom has 8 protons.
Q11fluency

The table gives the first ten elements and their proton counts. How many protons does every atom of helium have?

elementprotonshydrogen1helium2lithium3beryllium4boron5carbon6nitrogen7oxygen8fluorine9neon10an atom of helium

Typed answer

Answer

Accepted: 2 · 2 protons · two

Find helium in the table.
The table says 2.
So every helium atom has 2 protons.
Q12misconception

The table gives the first ten elements and their proton counts. Suki looks at an atom with 3 protons and 4 neutrons. She says: "3 protons and 4 neutrons make 7 particles, so this atom is nitrogen." Is Suki correct?

elementprotonshydrogen1helium2lithium3beryllium4boron5carbon6nitrogen7oxygen8fluorine9neon10
  1. A yes
  2. B no
Answer

Key: B — no

The number of protons decides which element an atom is.
The neutrons do not decide it, so the 4 neutrons are not added in.
The atom has 3 protons, so the table says lithium, and Suki is not correct.

Feedback per option

  • A Adding the neutrons in is the slip. Only the proton count decides the element: 3 protons, so the table says lithium.
  • B Only the proton count decides the element. The atom has 3 protons, so the table says lithium; the neutrons do not decide it.
Q13misconception

The table gives the first ten elements and their proton counts. Noor looks at an atom with 6 protons and 7 neutrons. She says: "This atom is carbon." Is Noor correct?

elementprotonshydrogen1helium2lithium3beryllium4boron5carbon6nitrogen7oxygen8fluorine9neon10Noor's atom: 6 protons and 7 neutrons
  1. A yes
  2. B no
Answer

Key: A — yes

The number of protons decides which element an atom is.
The atom has 6 protons, and the table says carbon.
The neutrons do not decide it, so Noor is correct.

Feedback per option

  • A Only the proton count decides the element, and 6 protons is carbon. The 7 neutrons do not change that.
  • B The 7 neutrons do not change the element. Only the proton count decides it, and 6 protons is carbon.
Your note · lesson 3: The proton count names the element
What to judge

Is this content better than the current alternative students have (PhysicsGraph / Edmentum)?

8/10 on:

  • Clear and concise language
  • Physics accuracy (read as chemistry accuracy here; his line as pasted for HS Physics)
  • No "clangers" (content that causes a problematic misconception)
  • Appropriate questions
  • Initial testing
  • Expansion into harder questions (no exam)
  • The tasks should use similar language to that of the lesson

Gut check: better than the alternative? Would a student benefit? Full criteria

Lesson 4 of 5Author: definitely a video174 words · about 1:27

Change the proton count, change the element

MAT-051b · Changing the proton count changes the element — Explain why adding or removing a proton from an atom changes it into a different element.

Script
SayScreen
Imagine a carbon atom with 6 protons in its nucleus.[the carbon atom; its six protons counted off]
Now imagine one more proton is pushed in: 7 protons. Is it still carbon?[a proton slides in; the count reads 7; question mark]
No, the atom is not carbon anymore.[label CARBON fades; question mark stays]
Here is the carbon atom, 6 protons, and one proton goes into the nucleus.[before drawing; the loose proton with its arrow]
Count again: 7 protons. Row 7 in the table says nitrogen.[after drawing; the seven protons counted off; row 7 lit]
So the atom is now nitrogen, not carbon.[the label switches CARBON → NITROGEN; chip: 7 PROTONS nitrogen]
Now consider an oxygen atom with 8 protons, and one proton comes out.[the oxygen atom; a proton drawn out along an arrow]
Count again: 7 protons, so the oxygen atom has become a nitrogen atom.[the count reads 7; label OXYGEN → NITROGEN]
Now imagine a neutron is added to a carbon atom instead.[the carbon atom; an open circle slides in]
The proton count is still 6, so the atom is still carbon.[the six protons counted off; label STILL CARBON]
Changing the proton count takes enormous force, so it happens inside stars.[a star]
On a bench, a carbon atom stays carbon.[a bench, label STAYS CARBON]
So, change the proton count, and you change the element.[the rule slide: the carbon-to-nitrogen pair; nothing else printed]
Adding or removing a neutron leaves the element the same.[the neutron pair; label STILL CARBON]
So the carbon atom with one extra proton has 7 protons, and 7 protons make it nitrogen.[the after drawing, labeled NITROGEN]
Okay, now your turn.[closing screen: bullets — • Change the proton count, and you change the element • Add or remove a neutron, and the element stays the same]

“Okay, now your turn.” — the attached question

video

One proton is pushed into a carbon atom's nucleus, making 7 protons. What has the atom become?

  1. A still carbon
  2. B nitrogen
  3. C oxygen
Answer

Key: B — nitrogen

The number of protons decides which element an atom is.
The atom now has 7 protons.
Every atom with 7 protons is nitrogen.

Feedback per option

  • A Carbon means 6 protons; with 7 protons the atom is not carbon anymore.
  • B 7 protons is nitrogen: the proton count changed, so the element changed.
  • C Oxygen means 8 protons; the atom has 7 protons.

Quiz after the video — the mastery check, 10 items

Q1recall

Filled circles marked + are protons, open circles are neutrons, small dark dots marked − are electrons. The table gives the first ten elements and their proton counts. Count the protons: which element is this atom?

+++−−−elementprotonshydrogen1helium2lithium3beryllium4boron5carbon6nitrogen7oxygen8fluorine9neon10
  1. A beryllium
  2. B lithium
  3. C helium
Answer

Key: B — lithium

Count only the filled circles marked plus: 3 protons.
Find 3 in the table: lithium.
So the atom is lithium.

Feedback per option

  • A Beryllium has 4 protons; this atom has 3 filled circles marked plus.
  • B 3 protons: the table says lithium.
  • C Helium has 2 protons; this atom has 3 filled circles marked plus.
Q2what

The table gives the first ten elements and their proton counts. This atom has 7 protons, and one proton is taken out of its nucleus. Which element is the atom now?

+++++++−−−−−−−+one proton taken outelementprotonshydrogen1helium2lithium3beryllium4boron5carbon6nitrogen7oxygen8fluorine9neon10
  1. A carbon
  2. B nitrogen
  3. C oxygen
Answer

Key: A — carbon

The atom had 7 protons, and one is taken out: 6 protons.
The number of protons decides the element.
Find 6 in the table: carbon.

Feedback per option

  • A Take one proton from 7 protons: 6 protons, and the table says carbon.
  • B Nitrogen means 7 protons; the atom now has 6 protons.
  • C Oxygen means 8 protons; the atom now has 6 protons.
Q3why

A boron atom has 5 protons. One proton is added to its nucleus. Explain why the atom is no longer boron.

Starter: The number of protons…

Answer

Model answer · ['the number of protons decides the element', 'the atom now has 6 protons, not 5', "6 protons is carbon (or: is not boron's count)"] points

The number of protons decides which element an atom is.
Boron means 5 protons.
The atom now has 6 protons.
Every atom with 6 protons is carbon, so the atom is carbon, not boron.
Q4why

One proton is taken out of a neon atom. Why is the atom now a different element?

  1. A The proton count decides the element, and it changed.
  2. B A lighter nucleus always means a different element.
  3. C Losing a particle of any kind from the nucleus changes the element.
Answer

Key: A — The proton count decides the element, and it changed.

The number of protons decides which element an atom is.
The neon atom had 10 protons and now has 9 protons.
Every atom with 9 protons is fluorine, so the atom is a different element.

Feedback per option

  • A The proton count decides the element: 10 protons became 9 protons, a different element's count.
  • B A nucleus can lose a neutron and stay the same element; only the proton count decides.
  • C Losing a neutron does not change the element; losing a proton does, because the proton count decides.
Q5misconception

Levi says: "Add one neutron to a fluorine atom, and it becomes a different element." Is Levi correct?

  1. A yes
  2. B no
Answer

Key: B — no

The number of protons decides which element an atom is.
Adding a neutron leaves the proton count at 9.
Every atom with 9 protons is fluorine, so the atom is still fluorine, and Levi is not correct.

Feedback per option

  • A A neutron does not change the element. The atom still has 9 protons, so it is still fluorine.
  • B Only the proton count decides the element. The atom still has 9 protons, so it is still fluorine.
Q6what

The table gives the first ten elements and their proton counts. This atom has 8 protons, and one neutron is added to its nucleus. Which element is the atom now?

++++++++−−−−−−−−one neutron addedelementprotonshydrogen1helium2lithium3beryllium4boron5carbon6nitrogen7oxygen8fluorine9neon10
  1. A fluorine
  2. B oxygen
  3. C nitrogen
Answer

Key: B — oxygen

A neutron was added, so the proton count did not change: still 8 protons.
The number of protons decides the element.
Find 8 in the table: oxygen, the same as before.

Feedback per option

  • A Fluorine means 9 protons; the atom still has 8 protons, because a neutron was added, not a proton.
  • B The proton count is still 8 protons, and 8 protons is oxygen.
  • C Nitrogen means 7 protons; the atom still has 8 protons.
Q7transfer

The table gives the first ten elements and their proton counts. This atom has 6 protons, and two protons are added to its nucleus. Which element is the atom now?

++++++−−−−−−++two protons addedelementprotonshydrogen1helium2lithium3beryllium4boron5carbon6nitrogen7oxygen8fluorine9neon10
  1. A nitrogen
  2. B oxygen
  3. C carbon
Answer

Key: B — oxygen

The atom had 6 protons, and two are added: 8 protons.
The number of protons decides the element.
Find 8 in the table: oxygen.

Feedback per option

  • A Nitrogen means 7 protons; the atom gained two protons, so it has 8 protons.
  • B 6 protons and two more make 8 protons, and the table says oxygen.
  • C Carbon means 6 protons; the atom now has 8 protons.
Q8transfer

The table gives the first ten elements and their proton counts. This atom has 9 protons, and one proton is added to its nucleus. Which element is the atom now?

+++++++++−−−−−−−−−+one proton addedelementprotonshydrogen1helium2lithium3beryllium4boron5carbon6nitrogen7oxygen8fluorine9neon10
  1. A neon
  2. B oxygen
  3. C fluorine
Answer

Key: A — neon

The atom had 9 protons, and one is added: 10 protons.
The number of protons decides the element.
Find 10 in the table: neon.

Feedback per option

  • A 9 protons and one more make 10 protons, and the table says neon.
  • B Oxygen means 8 protons; the atom now has 10 protons.
  • C Fluorine means 9 protons; the atom now has 10 protons.
Q9what

Which one change turns an atom of one element into an atom of a different element?

  1. A adding a neutron to its nucleus
  2. B adding an electron to the outside of its nucleus
  3. C adding a proton to its nucleus
Answer

Key: C — adding a proton to its nucleus

The number of protons decides which element an atom is.
Only adding or removing a proton changes that number.
So adding a proton turns the atom into a different element.

Feedback per option

  • A Adding a neutron leaves the proton count the same, so the element stays the same.
  • B Adding an electron leaves the proton count the same, so the element stays the same.
  • C Adding a proton changes the proton count, and the proton count decides the element.
Q10transfer

The table gives the first ten elements and their proton counts. Under it is one atom's proton count. How many protons must be added to make this atom an oxygen atom?

elementprotonshydrogen1helium2lithium3beryllium4boron5carbon6nitrogen7oxygen8fluorine9neon10this atom: 4 protons

Typed answer

Answer

Accepted: 4 · 4 protons · four

Oxygen means 8 protons.
The atom has 4 protons.
8 protons take away 4 protons is 4 protons, so 4 protons must be added.
Your note · lesson 4: Change the proton count, change the element
What to judge

Is this content better than the current alternative students have (PhysicsGraph / Edmentum)?

8/10 on:

  • Clear and concise language
  • Physics accuracy (read as chemistry accuracy here; his line as pasted for HS Physics)
  • No "clangers" (content that causes a problematic misconception)
  • Appropriate questions
  • Initial testing
  • Expansion into harder questions (no exam)
  • The tasks should use similar language to that of the lesson

Gut check: better than the alternative? Would a student benefit? Full criteria

Lesson 5 of 5Author: could do without a video198 words · about 1:39

Protons and electrons balance in a neutral atom

MAT-052 · A neutral atom has equal numbers of protons and electrons — Work out the number of electrons in a neutral atom given its number of protons.

Script
SayScreen
An atom of oxygen has 8 protons, and each proton carries a positive charge.[the oxygen atom; its eight protons counted off, plus marks glowing]
Yet an ordinary oxygen atom has no overall charge at all. Something must cancel the positives.[label: NO OVERALL CHARGE; question mark]
How many electrons does the atom have?[the rings, empty, with a question mark]
It has 8 electrons.[8 dots appear faintly on the rings]
Each proton carries one positive charge, each electron carries one negative charge, and a neutron carries no charge.[three chips: PROTON +, ELECTRON −, NEUTRON no charge]
One positive charge and one negative charge cancel each other out.[a + and a − slide together and fade]
The oxygen atom's 8 protons carry 8 positive charges.[tally: 8 plus marks]
To cancel 8 positive charges, the atom needs 8 negative charges, so it needs 8 electrons.[8 minus marks line up under the pluses; the 8 dots on the rings brighten]
8 positive charges and 8 negative charges cancel, so the atom has no overall charge.[the pairs fade; label NO OVERALL CHARGE]
An atom with no overall charge is called a neutral atom.[chip: NEUTRAL ATOM]
In a neutral atom the number of electrons equals the number of protons.[electrons = protons]
Now consider a neutral lithium atom: 3 protons, so 3 electrons.[the lithium atom with its counts]
And a neutral neon atom: 10 protons, so 10 electrons.[the neon atom with its counts]
So, in a neutral atom the positive charges and the negative charges cancel, and the number of electrons equals the number of protons.[the rule slide: the oxygen tally, 8 pluses and 8 minuses; chip NEUTRAL ATOM; nothing else printed]
So the oxygen atom has 8 protons and 8 positive charges, and 8 electrons cancel them.[the complete oxygen atom, 8 dots on the rings]
Okay, now your turn.[closing screen: one line — "In a neutral atom the number of electrons equals the number of protons."]

“Okay, now your turn.” — the attached question

video

An oxygen atom has 8 protons and no overall charge. How many electrons does it have?

  1. A 0
  2. B 8
  3. C 16
Answer

Key: B — 8

Each proton carries one positive charge: 8 positives.
Each electron carries one negative charge, and one of each cancels.
So the neutral oxygen atom has 8 electrons.

Feedback per option

  • A With no electrons the 8 positive charges would not be cancelled.
  • B 8 positive charges need 8 negative charges, so 8 electrons.
  • C The neutrons carry no charge, so only the 8 protons need cancelling: 8 electrons.

Quiz after the video — the mastery check, 11 items

Q1recall

Which charge does each electron carry?

  1. A positive
  2. B negative
  3. C none
Answer

Key: B — negative

Each electron is drawn with a minus mark.
The minus mark means a negative charge.
So each electron carries one negative charge.

Feedback per option

  • A Each proton carries the positive charge; an electron carries a negative charge.
  • B Each electron carries one negative charge: that is what its minus mark means.
  • C A neutron carries no charge; an electron carries a negative charge.
Q2term

An atom with no overall charge is called a…

Typed answer

Answer

Accepted: neutral atom · a neutral atom · neutral

An atom with no overall charge is called a neutral atom.
In a neutral atom the number of electrons equals the number of protons.
Q3term

A scientist calls an atom a neutral atom. What does she mean?

  1. A The atom has no overall charge.
  2. B The atom has no neutrons in its nucleus.
  3. C The atom has no electrons on its rings.
Answer

Key: A — The atom has no overall charge.

An atom with no overall charge is called a neutral atom.
Its protons' positive charges and its electrons' negative charges cancel.
So the scientist means the atom has no overall charge.

Feedback per option

  • A A neutral atom has no overall charge: its positives and negatives cancel.
  • B Neutral is about charge, not about neutrons. Neutrons carry no charge, so their number does not decide whether the atom is neutral.
  • C A neutral atom has electrons: as many as it has protons.
Q4scaffold

A neutral fluorine atom has 9 protons. How many positive charges do its protons carry?

Typed answer

Answer

Accepted: 9 · 9 positive charges · nine

Each proton carries one positive charge.
The atom has 9 protons.
So its protons carry 9 positive charges.
Q5scaffold

The neutral fluorine atom has 9 positive charges. How many negative charges are needed to cancel them?

Typed answer

Answer

Accepted: 9 · 9 negative charges · nine

One positive charge and one negative charge cancel each other out.
There are 9 positive charges.
So 9 negative charges are needed.
Q6scaffold

The neutral fluorine atom needs 9 negative charges. How many electrons does it have?

Typed answer

Answer

Accepted: 9 · 9 electrons · nine

Each electron carries one negative charge.
The atom needs 9 negative charges.
So the neutral fluorine atom has 9 electrons.
Q7bare

A neutral atom has 4 protons. How many electrons does it have?

Typed answer

Answer

Accepted: 4 · 4 electrons · four

In a neutral atom the number of electrons equals the number of protons.
The atom has 4 protons.
So it has 4 electrons.
Q8bare

The table gives the first ten elements and their proton counts. How many electrons does a neutral atom of nitrogen have?

elementprotonshydrogen1helium2lithium3beryllium4boron5carbon6nitrogen7oxygen8fluorine9neon10a neutral atom of nitrogen

Typed answer

Answer

Accepted: 7 · 7 electrons · seven

Find nitrogen in the table: 7 protons.
In a neutral atom the number of electrons equals the number of protons.
So a neutral nitrogen atom has 7 electrons.
Q9bare

Filled circles marked + are protons, open circles are neutrons, small dark dots marked − are electrons. This neutral atom is drawn with its electrons left off the ring. How many electrons does it have?

+++++

Typed answer

Answer

Accepted: 5 · 5 electrons · five

Count the filled circles marked plus: 5 protons.
In a neutral atom the number of electrons equals the number of protons.
So this atom has 5 electrons; the 6 open circles are neutrons and change nothing.
Q10bare

Filled circles marked + are protons, open circles are neutrons, small dark dots marked − are electrons. This neutral atom is drawn with its electrons left off the ring. How many electrons does it have?

++

Typed answer

Answer

Accepted: 2 · 2 electrons · two

Count the filled circles marked plus: 2 protons.
In a neutral atom the number of electrons equals the number of protons.
So this atom has 2 electrons.
Q11misconception

Anya says: "A neutral atom with 6 protons and 7 neutrons has 13 electrons, one for each particle in the nucleus." Is Anya correct?

  1. A yes
  2. B no
Answer

Key: B — no

Each proton carries one positive charge, and a neutron carries no charge.
Only the 6 positive charges need cancelling, so 6 negative charges are needed.
The neutral atom has 6 electrons, not 13, and Anya is not correct.

Feedback per option

  • A Neutrons carry no charge, so they need no electrons to cancel them. Only the 6 protons do, so the atom has 6 electrons.
  • B Only the 6 protons carry charge, so only 6 electrons are needed to cancel them. The neutral atom has 6 electrons.
Your note · lesson 5: Protons and electrons balance in a neutral atom
What to judge

Is this content better than the current alternative students have (PhysicsGraph / Edmentum)?

8/10 on:

  • Clear and concise language
  • Physics accuracy (read as chemistry accuracy here; his line as pasted for HS Physics)
  • No "clangers" (content that causes a problematic misconception)
  • Appropriate questions
  • Initial testing
  • Expansion into harder questions (no exam)
  • The tasks should use similar language to that of the lesson

Gut check: better than the alternative? Would a student benefit? Full criteria

Summary video · everything taught, in order, just before the PP100183 words · about 1:32

Summary: Inside the atom

Script, part 1 (95 words)
SayScreen
Here is everything we found out about what is inside the atom.[a still: the opened carbon atom]
One carbon atom is the smallest piece that is still carbon.[the one gray circle]
Every atom contains three kinds of smaller particle: protons, neutrons and electrons.[the opened circle; the three chips]
Protons are the filled circles marked plus, neutrons are the open circles, and electrons are the small dark dots marked minus.[the key]
Protons and neutrons sit together in a tiny center called the nucleus.[the lithium atom; the dashed ring; chip NUCLEUS]
Protons carry a positive charge; neutrons carry no charge.[a proton's plus glows; an open circle with nothing]
And electrons move around the outside of the nucleus and carry a negative charge.[the dots on the rings, minus marks glowing]
Okay, now your turn.[closing screen: bullets — • Every atom: protons, neutrons and electrons • Protons and neutrons sit in the nucleus • Protons: positive charge; neutrons: no charge • Electrons: negative charge, outside the nucleus]

“Okay, now your turn.” — the check question between the parts

video

Which particle inside an atom carries a negative charge?

  1. A a proton
  2. B a neutron
  3. C an electron
Answer

Key: C — an electron

Protons carry a positive charge; neutrons carry no charge.
Electrons carry a negative charge.

Feedback per option

  • A A proton carries a positive charge.
  • B A neutron carries no charge.
  • C An electron carries a negative charge and moves around the outside of the nucleus.
Script, part 2 (88 words)
SayScreen
Here is everything we found out about what makes an atom one element and not another.[a still: the two atoms, 6 PROTONS and 7 PROTONS]
The number of protons decides which element an atom is.[the two atoms: 6 PROTONS, carbon; 7 PROTONS, nitrogen]
Count the protons, find the number in the table, and read off the element.[the ten-row table; a row lit]
Change the proton count, and you change the element.[the before-and-after pair]
But adding or removing a neutron leaves the element the same.[the neutron pair; label STILL CARBON]
An atom with no overall charge is called a neutral atom.[chip NEUTRAL ATOM]
In a neutral atom the number of electrons equals the number of protons.[electrons = protons]
Okay, now your turn.[closing screen: bullets — • The number of protons decides the element • Change the proton count, and you change the element • Neutral atom: electrons = protons]

“Okay, now your turn.” — the two questions after part 2

video

An atom has 8 protons in its nucleus. Which element is it?

  1. A carbon
  2. B nitrogen
  3. C oxygen
Answer

Key: C — oxygen

The number of protons decides which element an atom is.
Every atom with 8 protons is oxygen.

Feedback per option

  • A Every atom with 6 protons is carbon.
  • B Every atom with 7 protons is nitrogen.
  • C Every atom with 8 protons is oxygen: the proton count decides the element.
video

A neutral nitrogen atom has 7 protons. How many electrons does it have?

  1. A 0
  2. B 7
  3. C 14
Answer

Key: B — 7

In a neutral atom the positive and negative charges cancel.
So the number of electrons equals the number of protons.
7 protons, so 7 electrons.

Feedback per option

  • A With no electrons the 7 positive charges would not be cancelled.
  • B In a neutral atom the number of electrons equals the number of protons: 7.
  • C The neutrons carry no charge and need no cancelling; 7 protons need 7 electrons.
Your note · the summary video
What to judge

Is this content better than the current alternative students have (PhysicsGraph / Edmentum)?

8/10 on:

  • Clear and concise language
  • Physics accuracy (read as chemistry accuracy here; his line as pasted for HS Physics)
  • No "clangers" (content that causes a problematic misconception)
  • Appropriate questions
  • Initial testing
  • Expansion into harder questions (no exam)
  • The tasks should use similar language to that of the lesson

Gut check: better than the alternative? Would a student benefit? Full criteria

Applied without asking

Rulings you have already given; in force on every card above, not re-asked.

The topic’s fixed wording (the lexicon the scripts repeat)
  • One carbon atom is the smallest piece that is still carbon.
  • Every atom contains three kinds of smaller particle: protons, neutrons and electrons.
  • Protons and neutrons sit together in a tiny center called the nucleus.
  • Protons carry a positive charge; neutrons carry no charge.
  • Electrons move around the outside of the nucleus and carry a negative charge.
  • The number of protons decides which element an atom is.
  • Change the proton count, and you change the element.
  • An atom with no overall charge is called a neutral atom.
  • In a neutral atom the number of electrons equals the number of protons.

Scripts, questions and quizzes are read from the course content as it stands today; the student site for this topic is here.