Question

2.5 g of the carbonate of a metal was treated with 100 mL of IN H2SO4. After the completion of the reaction, the solution was boiled *** to expel CO2 and was then titrated against IN NaOH solution. The volume of alkali that would be consumed, if the equivalent weight of the metal is 20, is

(a) 50 mL

(b) 25 mL

(c) 75 mL

(d) 100 mL

Answer 1

Correct option (a) 50 mL

Explanation:

Equivalent weight of metal carbonate= 20+30=50

2.5 g of metal carbonate = 2.5/50 = 0.05 eq.

Number of equivalents of H2SO4 that would have reacted = 0.05

Number of equivalents of H2SO4 taken

= 100 x1/1000 = 0.1

Number of equivalents of H2SO4 *** unreacted

= 0.1 - 0.05 = 0.05 eq.

∴ Number of equivalent of alkali consumed = 0.05 eq.