Question

The carbonate that will not decompose heating is:
A. $N{a_2}C{O_3}$
B. $CaC{O_3}$
C. $BaC{O_3}$
D. $SrC{O_3}$

Answer 1

Hint: Many carbonates decompose on heating to give metal oxides and carbon dioxide gas except the alkali metal (group 1 metals) carbonates.

Complete step-by-step answer:
Decomposition is defined as the process or effect of simplifying a single chemical substance into two or more particles. Decomposition is normally considered and defined as the exact opposite of chemical synthesis.
In a nutshell, decomposition reaction is a kind of chemical reaction where a single compound splits down into two or more elements or new compounds. Such reactions most often involve a source of energy such as light or electricity which can break the bonds in the compounds to be decomposed.
As we know a combination reaction is a chemical reaction in two or more substances combined together to produce a new compound. Whereas in a decomposition reaction, the combination between constituents is broken down to form multiple products.
Another important point to be noted is that decomposition may be exothermic as well as endothermic.
Now the type of decomposition here is thermal decomposition. A thermal decomposition reaction is the decomposition reaction which is activated by thermal energy. The reaction is generally endothermic as energy is required to break the chemical bonds in order to separate the constituent elements.
Now coming back to the question where it is asked which metal carbonate will not decompose on heating. All alkali metal (IA group) carbonates (except $L{i_2}C{O_3}$​ ) are highly stable and do not decompose on heating.
Whereas, the alkaline earth metal (IIA group) carbonates decompose on heating giving metal oxide and carbon dioxide. The only alkali metal here is $N{a_2}C{O_3}$. Thus$N{a_2}C{O_3}$will not decompose on heating.
Therefore option A is the correct option.

Note: Ionic bonding is defined as the total transfer of valence electrons between atoms. It is a kind of chemical bond that produces two oppositely charged ions. Ionic bonds are stronger than covalent bonds.