Fundamental particles

Question 1

What are the three sub-atomic particles of an atom?

Answer 1

• Protons
• Neutrons
• Electrons

Question 2

What is the charge and mass of a proton?

Answer 2

• Charge = +1
• Mass = 1

Question 3

What is the charge and mass of a neutron?

Answer 3

• Charge = 0
• Mass = 1

Question 4

What is the charge and mass of a electron?

Answer 4

• Charge = -1
• Mass = 1/2000

Question 5

What is the atomic mass number?

Answer 5

The number of protons in the nucleus

Question 6

What is the mass number?

Answer 6

The number of protons and neutrons in the nucleus

Question 7

What is an isotope?

Answer 7

An element that contains the same number of electrons and protons but different numbers of neutrons. They have the same atomic number but different mass number. They have different properties (e.g boiling points).

Question 8

What is the symbol for a proton?

Answer 8

p+

Question 9

What is the symbol for a neutron

Answer 9

n⁰

Question 10

What is the symbol for a electron

Answer 10

e^-

Question 11

What is the chemistry of an atom determined by?

Answer 11

How the electrons behave

Question 12

What properties do chemists believe electrons have?

Answer 12

Chemists believe that electrons have some properties of particles, some of waves, and at other times act as clouds of charge.

Question 13

What is an orbital?

Answer 13

A region were two electrons can exist

Question 14

What are nucleons?

Answer 14

The protons and neutrons that live in the centre of the atom.

Question 15

What is the letter that represents the mass number?

Answer 15

A

Question 16

What is the letter that represents the atomic number?

Answer 16

Z

Question 17

The number of electrons is the same as the number of…

Answer 17

protons

Question 18

All atoms of the same element have the same number of what?

Answer 18

protons

Question 19

What did John Dalton suggest at the start of the 19th centurary?

Answer 19

That elements were composed of indivisible atoms (solid spheres). All atoms of a particular element had the same mass and atoms of different elements and different masses.

Question 20

What did Robert Boyle propose in 1661?

Answer 20

Chemical elements could not be made simpler.

Question 21

What did Henri Becquerel discover in 1896?

Answer 21

Radioactivity

Question 22

What did the discovery of radioactivity prove?

Answer 22

That atoms can divide.

Question 23

What did JJ Thomson discover in 1896?

Answer 23

The electron (the first sub-atomic particle to be discovered)

Question 24

What did the discovery of the electron disprove?

Answer 24

That atoms are not solid or indivisible.

Question 25

What was the history of the model of the atom?

Answer 25

* 'Solid sphere' structure * 'Plum pudding' model * Nuclear model * Niels Bohr's model * ​Electron cloud model

Question 26

Draw each model of the atom in time order

Answer 26

[https://www.siyavula.com/read/science/grade-10/the-atom/04-the-atom-02](https://www.siyavula.com/read/science/grade-10/the-atom/04-the-atom-02)

Question 27

What did Ernest Rutherford conduct in 1909?

Answer 27

Gold foil experiment

Question 28

What was the gold foil experiment?

Answer 28

Positively charged alpha particles were fired at a very thin sheet of gold. Most of the particles passed straight through the gold foil with only a small number being deflected back. This disproved the plum pudding model

Question 29

Watch this!

Answer 29

[https://www.youtube.com/watch?v=thnDxFdkzZs](https://www.youtube.com/watch?v=thnDxFdkzZs)

Question 30

Watch this!

Answer 30

[https://www.youtube.com/watch?v=xazQRcSCRaY](https://www.youtube.com/watch?v=xazQRcSCRaY)