C1. Atomic structure

Question 1

What is the structure of a nucleus?

Answer 1

The structure of the atom as a central nucleus (containing protons and neutrons) surrounded by electrons moving in discrete shells/energy levels

Question 2

Relative charge of subatomic particles

Answer 2

Proton=+1 Neutron=0 and Electron=-1

Question 3

Relative mass of subatomic particles

Answer 3

Proton=1 Neutron=1 and Electron= 1/1836

Question 4

Use the atomic number to write the electron configurations of the first 20 elements in the
Periodic Table (H to Ca) in comma-separated format (e.g. 2,8,8,1 for a potassium atom).

Answer 4

First shell has 2 electrons
Second shell onwards has 8

Question 5

What is an isotope?

Answer 5

Isotopes are atoms of an element with the same number of protons but a different numbers of neutrons

Question 5

What is Ar and how to calculate?

Answer 5

Sum of all the masses/ relative intensity
Ar is defined as the average mass of an atom of an element compared to 1/12 the mass of a carbon-12 atom