10.3 Halide ions reactions

Question 1

Cl reaction with H2SO4 observations:

Answer 1

HCl forms steamy white fumes

Question 2

Br reaction with H2SO4 observations:

Answer 2

Orange vapour from Br2 liquid
choking gas from SO2

Question 3

I reaction with H2SO4 observations:

Answer 3

Yellow solid (sulfur)
Purple vapour from solid Iodine

Question 4

I 2nd reaction with H2SO4 observations:

Answer 4

Foul smelling H2S

Question 5

solid NaCl + H2SO4 equation

Answer 5

Cl- + H2SO4 —> HCl + HSO4-
not redox, ox. remains the same
Cl- too weak to reduce S, so it acts as a base

Question 6

solid NaBr + H2SO4 equation

Answer 6

2H+ + 2Br- + H2SO4 —> SO2 + 2H2O + Br2
S reduced from 6+ to 4+
redox reaction
Br strong enough reducing agent

Question 7

solid NaI + H2SO4 equation

Answer 7

6I- + H2SO4 + 6H+ —> 3I2 + S + 4H2O
S reduced from 6+ to 0

Question 8

solid NaI + H2SO4 second equation

Answer 8

8I- + H2SO4 + 8H+ —> H2S + 4H2O + 4I2
S reduced from +6 to -2

Question 9

Product of Cl- with H2SO4

Answer 9

HSO4-

Question 10

Product of Br- with H2SO4

Answer 10

SO2

Question 11

Product of I- with H2SO4
(Both reactions)

Answer 11

S
H2S