Sodium salt of an organic acid 'X' produces effervescence with conc. H2SO4. 'X' reacts with the acidified aqueous CaCl2 solution to give a white precipitate which decolourizes acidic solution of KMnO4. 'X' is: HCOONa, CH3COONa, Na2C2O4, C6H5COONa
Na2C2O4
CH3COONa
HCOONa
C6H5COONa
Solution:
Sodium salt of an organic acid 'X' is sodium oxalate Na2C2O4. It gives effervescence of CO2 gas with conc. H2SO4. Na2C2O4 + H2SO4 → Na2SO4 + H2O + CO↑ + CO2↑