Question

Which of the following represents calcium chlorate?
A) $CaCl{O_2}$
B) $Ca{(ClO_4)}_2$
C) $Ca{\left( {Cl{O_3}} \right)_2}$
D) $Ca{(ClO_2)}_2$

Answer 1

Calcium chlorate is basically a calcium salt of chloric acid. It exists as a white crystalline solid. It leads to the formation of a highly flammable mixture when combined with combustible materials and this mixture can even be ignited via friction. When it comes in contact with strong sulfuric acid, it can cause fires and explosions.

Complete answer:
Calcium chlorate is generally produced by passing the chlorine gas ($C{l_2}$) to a hot suspension of calcium hydroxide ($Ca{\left( {OH} \right)_2}$) in water, thereby, producing calcium hypochlorite ($CaHCl{O_3}$), which dissociates on heating with excess of chlorine to yield calcium chlorate ($Ca{\left( {Cl{O_3}} \right)_2}$) and calcium chloride ($CaC{l_2}$). The chemical reaction for the production of calcium chlorate can be represented as follows:
$6{\text{ }}Ca{\left( {OH} \right)_2} + {\text{ }}6{\text{ }}C{l_2} \to Ca{\left( {Cl{O_3}} \right)_2} + {\text{ }}5{\text{ }}CaC{l_2} + {\text{ }}6{\text{ }}{H_2}O$
Theoretically, electrolysis of hot solution of calcium chloride will yield chlorate, in a process similar to the one that is utilised for the production of sodium chlorate.
Thus, Calcium chlorate has the chemical formula of $Ca{\left( {Cl{O_3}} \right)_2}$.

Therefore, Option C, i.e. $Ca{\left( {Cl{O_3}} \right)_2}$ represents calcium chlorate.

Note: Calcium chlorate is generally used in photography, occasionally in pyrotechnics (as an oxidizer or pink flame colorant), and as a herbicide (like sodium chlorate). Its hygroscopic nature and even incompatibility with some other common pyrotechnic materials (like sulfur) limit its use in these applications.