Question

3. A compound of a metal 'X' when heated give another compound of the same metal and a gas is
evolved with brisk effervescence. When the gas evolved is passed through the lime water we get
back the same compound which we heated. The meta: 'X' is:-
(a) Cu
(b) Na
(c) Ca
(d) CaCO3​

Answer 1

kon se class ka q h ye mai 7th me hu