1.2 Relative atomic mass & electronic charge

Question 1

What is the relative atomic
mass?

Answer 1

The average mass value which takes the mass and abundance of isotopes of an element into account, on a scale where the mass of Carbon-12 is 12.

Question 2

Give the electronic configuration of
He (2)

Answer 2

2

Question 3

Give the electronic configuration of
Be (4)

Answer 3

2, 2

Question 4

Give the electronic configuration of
F (9)

Answer 4

2, 7

Question 5

Give the electronic configuration of
Na (11)

Answer 5

2, 8, 1

Question 6

What are ions?

Answer 6

Ions are charged particles. They are formed when atoms lose electrons (positive ions) or gain (negative ions) electrons.

E.g. The sodium positive ion, Na+, has an electronic configuration of 2,8 (same as Ne). An atom of sodium has lost one electron.

Question 6

Give the electronic configuration of
Ca (20)

Answer 6

2, 8, 8, 2

Question 8

State the relative masses and
relative charges of the proton,
neutron and electron

Answer 8

Masses
Proton: 1
Neutron: 1
Electron: 1/2000

Charges
Proton: +1
Neutron: 0
Electron: -1

Question 9

Explain why atoms have no overall charge

Answer 9

They have the same number of electrons and protons