June 2017

Question 1

1.3. Explain why the second ionisation energy of aluminium is greater than the first ionisation energy of aluminium. (1)

Answer 1

the electron is being removed from a positive ion

Question 2

2.3. Explain how the abundance of each isotope is determined in a TOF mass spectrometer. (2)

Answer 2

(1) Ions hit the detector and accept electrons causing current to flow
(2) Bigger current = higher abundance of that ion

Question 3

7.1. State the strongest type of intermolecular force in HI (1)

Answer 3

VDW forces

Question 4

7.2. Explain why the boiling point of HF is greater than the boiling point of HCl (2)

Answer 4

(1) HF has hydrogen bonding
(2) Which is stronger than the forces between HCl molecules

Question 5

7.3. Explain why the boiling points increase from HCl to HI (2)

Answer 5

(1) Size of molecule increases (from HCl to HI)
(2) So van der Waals’ forces (between molecules) become stronger

Question 6

9.2. A student added a few drops of conc. sulfuric acid to solid sodium bromide. Give 2 observations that the student would make. (2)

Answer 6

Any two from:
- brown/orange gas
- misty fumes
- choking gas