CC3

Question 1

What was John Daltons theory

Answer 1

1) All matter is made up of tiny particles called atoms

2) Atoms are tiny hard spheres that cannot be broken down

3) Atoms in an element are all identical

Question 2

What was JJ Thompson theory

Answer 2

Plum pudding model
1) Atoms weren’t solid spheres
2) Discovered electrons
3) The model suggested that the atom was a ball of positive charge with negative electrons engraved in it

Question 3

What was Ernest Rutherford theory

Answer 3

Alpha scattering
1) Fired particles on a gold foil sheet
2) Particles went through, deflected and bounced back
3) Atoms were mostly empty space with a small positive central nucleus that contains mass

Question 4

What was Bohrs model

Answer 4

Electrons were seen as shells
Shells have fixed energy
Supported by scientists

Question 5

What are the 3 subatomic particles an atom is made of

Answer 5

Protons - heavy and positively charged
Neutrons - Heavy neutral
Electrons - Hardly any mass negatively charged

Question 6

What is the relative mass and relative charge of each subatomic particle

Answer 6

Proton: Mass 1: Charge +1
Neutron: Mass 1: Charge 0
Electron: Mass 1/1836: Charge -1

Question 7

What is the nucleus

Answer 7

Middle of the atom
Contains protons and neutrons
Has a positive charge because of protons
The whole mass of an atom is concentrated there
The nucleus is tiny compared to the atom

Question 8

What are electrons

Answer 8

Move around nucleus in shells
They are negatively charged

Question 9

What is the overall charge of the atom

Answer 9

Neutral, they have no overall charge as it has the same number of protons as electrons

Question 10

Which is the mass number and which is the atomic number

Answer 10

The top number and the biggest number are always the mass number. Shows number of protons and neutrons

The bottom number and smaller number is always an atomic number. Shows number of protons and electrons

Question 11

How do you work out the number of neutrons

Answer 11

Mass number - Atomic number

Question 12

What is an isotope

Answer 12

Isotopes are atoms of an element with different number of neutrons

Question 13

What is the relative atomic mass

Answer 13

The average mass number of isotopes

(The mass number)

Question 14

What is the formulae for relative atomic mass

Answer 14

RAM = (mass number of isotope 1 x percentage abundance of isotope 1) + (mass number of isotope 2 x percentage abundance of isotope 2) divide 100

Question 15

What is nuclear fission?

Answer 15

When the nucleus of a large atom such as uranium, splits into two smaller nuclei.

Question 16

Why did the periodic table get rearranged?

Answer 16

The elements in the periodic table used to be placed in order of the masses of their atoms. However, this caused some elements to be grouped with others that had very different properties. Because of this, a few elements were moved around so that elements with similar properties would be grouped together, making the periodic table no longer arranged by mass. As a result, the atomic number was created to correctly order each element.