The Atom

Question 1

What 3 subatomic particles make up an atom?

Answer 1

Protons, neutrons and electrons.

Question 2

What are the properties of a proton?

Answer 2

Heavy and positively charged.

Question 3

What are the properties of a neutron?

Answer 3

Heavy and neutral.

Question 4

What are the properties of an electron?

Answer 4

Have hardly any mass and are negatively charged.

Question 5

What is the relative mass of a proton?

Answer 5

1

Question 6

What is the relative mass of a neutron?

Answer 6

1

Question 7

What is the relative mass of an electron?

Answer 7

0.0005

Question 8

What is the relative charge of a proton?

Answer 8

+1

Question 9

What is the relative charge of a neutron?

Answer 9

0

Question 10

What is the relative charge of an electron?

Answer 10

-1

Question 11

What is in the nucleus of an atom?

Answer 11

Protons and neutrons.

Question 12

What charge does the nucleus have?

Answer 12

Positive charge (because of the protons).

Question 13

Where is almost the whole mass of the atom concentrated?

Answer 13

In the nucleus.

Question 14

How do electrons move around the nucleus?

Answer 14

In electron shells.

Question 15

How big are electrons?

Answer 15

Very small, but their shells cover a lot of space.

Question 16

How big is the nucleus?

Answer 16

Very small compared to the rest of the atom.

Question 17

What does the size of shells determine the size of?

Answer 17

The size of the atom.

Question 18

What is the atomic radius of an atom?

Answer 18

10 ^-10 m.

Question 19

What is the overall charge of atoms?

Answer 19

0 - they have no charge overall (unlike ions).

Question 20

Why do atoms have no overall charge?

Answer 20

Because they have the same number of protons as electrons.

The charge on electrons is the same size as the charge on protons, but opposite - so they cancel out.

Question 21

What is the nuclear symbol of an atom?

Answer 21

Everything here:
23
Na
11

Question 22

Which number is the mass / atomic number?

Answer 22

Top number = Mass number

Bottom number = Atomic number

Question 23

What does the atomic number tell you?

Answer 23

How many protons the atom has.

Question 24

What does every atom of an element have that is the same?

Answer 24

The number of protons.

Question 25

What does the atomic number tell you if the atom is neutral?

Answer 25

The number of protons is equal to the number of electrons, so the number of electrons equals the atomic number.

Question 26

What does the mass number tell you?

Answer 26

The total number of protons and neutrons in the atom.

Question 27

How can you work out the number of neutrons in an atom?

Answer 27

Subtract the atomic number from the mass number.