Question

Thermal stability of MCO3 is in order :

• A. BeCO3< MgCO3< CaCO3< SrCO3< BaCO3
• B. MgCO3< BeCO3< CaCO3< SrCO3< BaCO3
• C. CaCO3< SrCO3< BaCO3< BeCO3< MgCO3
• D. BaCO3< SrCO3< CaCO3< MgCO3< BeCO3

Answer 1

Answer: (A)

BeCO3< MgCO3< CaCO3< SrCO3< BaCO3

Answer 2

The stability of carbonates increases with increasing metallic character i.e. electropositive character. Down the group, ionisation energies decreases and thus electropositive

character increases