Question

Match the following

Types of chemical reaction	Chemical equation
(a) Combination reaction	$\left( {\text{i}} \right){\text{ }}CaC{O_3}{\text{ }} \to {\text{ }}CaO{\text{ }} + {\text{ }}C{O_2}$
(b) Decomposition reaction	$\left( {{\text{ii}}} \right){\text{ }}2{H_2}{\text{ }}O{\text{ }} \to {\text{ }}2{H_2}{\text{ }} + {\text{ }}{O_2}$
(c) Displacement reaction	$\left( {{\text{iii}}} \right){\text{ }}CaO{\text{ }} + {\text{ }}C{O_2}{\text{ }} \to {\text{ }}CaC{O_3}\;$
(d) Analysis reaction	$\left( {{\text{iv}}} \right){\text{ }}Fe(s) + {\text{ }}CuS{O_4}(aq.) \to FeS{O_4}(aq.) + Cu(s)$

A.a(ii), B(i), C(iv), d(iii)
B. a(i), b(ii), c(iii), d(iv)
C.a(iii), b(i), c(iv), d(ii)
D.a(iii), b(i), c(iii), d(iv)

Answer 1

To answer this question, you should recall the different types of chemical reactions. Chemical reactions are all around us, from the metabolism of food in our body to how the light we get from the sun is the results of chemical reactions.

Complete step by step answer:
Let us analyze the options systematically
1. Combination reaction: A combination reaction (also known as a synthesis reaction) is a reaction where two or more elements or compounds (reactants) combine to form a single compound (product). $Cao + C{O_2} \to CaC{O_3}$​, in this reaction calcium oxide is combined with carbon dioxide to form calcium carbonate.
2. Decomposition reaction: A Decomposition reaction is a reaction in which a single component breaks down into multiple products. Certain changes in energy in the environment have to be made like heat, light or electricity breaking bonds of the compound. Consider the example of the decomposition of calcium carbonate $CaC{O_{3}} \to CaO + C{O_2},$ in this reaction calcium carbonate is decomposed to calcium oxide and carbon dioxide.
3. Displacement reaction: A displacement reaction is the one wherein the atom or a set of atoms is displaced by another atom in a molecule.$Fe\left( s \right) + CuS{O_4}\left( {aq.} \right) \to FeS{O_{4}}\left( {aq} \right) + Cu\left( s \right),$ in this reaction Fe displaces copper to form ferric sulphate.
4. Analysis reaction: You can recognize this type of reaction by looking for a single reactant with multiple products. Decomposition reactions are also known as analysis reactions or chemical breakdowns. The opposite of this type of reaction is a synthesis in which simpler reactants combine to form a more complex product $2{H_2}O \to 2{H_2} + {O_2}$.

Hence, the correct answer is option C.

Note:
A substance is said to undergo a physical change when only the physical properties of the reactant change while chemical change refers to a substance combined with another to form a new substance. Atoms or ions or molecules which react to form a new substance are called reactants; the new atoms or molecules formed are products. Chemical changes are irreversible except by further chemical reactions.