X is a substance which liberates CO2 on treatment with concentrated H2SO4. A warm solution of X can decolorize acidified KMnO4. X is?

A. HCOOH
B. NaHCO3
C. FeCO3
D. H2C2O4

Correct Answer:

Option D – H2C2O4

Explanation

It should be noted that for X to liberate CO2, X must be a carbonate or an oxalate. Since X decolorizes KMnO4, X must be an oxalate. Therefore, X is H2C2O4.