Group 2 and 7

Question 1

Reaction of NaF with H2SO4

Answer 1

NaF+H2SO4 = NaHSO4 +HF
Observation: HF gives steamy fumes

Question 2

Reaction of NaCl with H2SO4

Answer 2

NaCl + H2SO4 = NaHSO4 + HCl
observation: steamy fumes

Question 3

NaBr + H2SO4=

Answer 3

NaHSO4 +HBr
Br- in HBr are oxidised further reducing sulphur from H2SO4 in SO2
Overall eq: H2SO4 + 2H+ + 2Br- =SO2 +2H2O +Br2
observation : An acidic gas SO2 is produced and brown fumes of bromine gas appears

Question 4

reaction of Iodide ions with H2SO4

Answer 4

NaI + H2SO4 = NaHSO4 + HI
Iodide ions are reduced to form SO2, S and H2S

2I- + 2H+ + H2SO4 =I2 + SO2 + 2H2O
Observation ; acidic gas and black solid of iodide forms

H2SO4 + 6H+ + 2I- = S + I2 +4H2O
Observation yellow sulfur solid and black solid of iodidse forms
H2SO4 + 8H+ + 2I- = I2 + H2S + 4H2O
observation bad eggy smell of H2S and black solid of iodide forms

Question 5

Reaction of Cl2 with an alkali

Answer 5

Cl2 + 2NaOH = NaClO + NaCl + H2O
NaClO is a component of household bleach