Chemistry Paper 1 Mistakes

Question 1

Which statement about the reactions of halogens with halide ions is correct?

A) I2 (aq) can oxidise Br- (aq)
B) Cl2 (aq) can reduce Br- (aq)
C) Br- (aq) can reduce cl2 (aq)
D) Cl- (aq) can oxidise I2 (aq)

Answer 1

C

Oxidising strength decreasing down the group
Reducing strength for the halides is increasing down the group

Question 2

A molecule has a molar mass of 2.658 x 10-23g. What is the possible formula of the gas?

A) CH4
B) O2
C) SO2
D) SO3

Answer 2

A

Workout relative formula mass of all options
Multiply the mass by avogadros
It sold give 16