Which of the carbonates given below is unstable in air and is kept in CO2 atomosphere to avoid decomposition?
(a) BeCO3 (b) MgCO3 (c) CaCO3 (d) BaCO3
(a)
BeCO3 is unstable to the extent that it is stable only in atomosphere of CO2.BeCO3 shows reversible reaction because stability o foxide formed is more than carbonates.
BeCO3⇌BeO+CO2
BeCO3 is unstable due to strong polarising effect of small Be2+ ion on the large polarisable carbonation . Moreover, an extrastability f the oxide achieved through lattice energy by opacking small cation with small oxide. Ion.