Physical Chemistry> When NaBr is heated with conc H2SO4 ,Br2 ...

When NaBr is heated with conc H2SO4 ,Br2 is produced but when NaCl is heated withconc H2SO4, HCl is produced. Why?

aditya kashyap , 11 Years ago

Grade upto college level

2 Answers

Gaurav

Last Activity: 10 Years ago

Hello Student
NaCl is a volatile solid. Less volatile liquid H2SO4 displaces the more volatile sodium chloride and hence there is no changed in oxidation state. Due to this it becomes a simple displacement reaction as
NaCl + H2SO4 à NaHSO4 +HCl
In case of NaBr, Br- acts as reducing agent fr H2SO4 and the sulphuric acid is reduced to sulphr ioxide by bromide ion which itself gets oxideised to give bromine free molecule.
2NaBr + 2H2SO4 à NaHSO4 + Br2 + SO2 + 2H2OHello Student

Kushagra Madhukar

Last Activity: 4 Years ago

Dear student,

NaCl is a volatile solid. Less volatile liquid H₂SO4 displaces the

more volatile sodium chloride and hence there is no changed in oxidation state. Due to this it becomes a simple displacement reaction as

NaCl + H₂SO₄ → NaHSO₄ +HCl

In case of NaBr, Br- acts as reducing agent fr H₂SO₄ and the sulphuric acid is reduced to sulphr ioxide by bromide ion which itself gets oxideised to give bromine free molecule.

2NaBr + 2H₂SO₄ → NaHSO₄ + Br₂ + SO₂ + 2H₂O

Hope it helps.

Thanks and regards,

Kushagra