NEET Chemistry The s-Block Elements Questions Solved


The compound X on heating gives a colourless gas. The residue is dissolved in water to obtain Y. Excess of CO2 is bubbled through aqueous solution of Y, Z is formed. Z on gentle heating gives back X. The compound X is-

(A) CaCO3                                           

(B) Na2CO3

(C) CaSO4.2H2O                                 

(D) K2CO3

(A). CaCO3XCaO+CO2, CaO+H2OCaOH2Y

 CaOH2Y+CO2excessCaHCO32Z

CaHCO32ZCaCO3X+H2O+CO2

Difficulty Level:

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