Question

Which of the following reactions is an example of decomposition reaction ?

• A. \(H_2 + I_2 \rightarrow 2HI\)
• B. \(NH_4CNO \rightarrow H_2NCONH_2\)
• C. \(NaOH + HCl \rightarrow NaCl + H_2O\)
• D. \(2KClO_3 \rightarrow 2KCl + 3O_2\)

Hint:

To quickly identify a decomposition reaction, look for the equation that has only one chemical species on the reactant (left) side and multiple species on the product (right) side.

Answer 1

The Correct Option is D

Step 1: Understanding the Concept:
A decomposition reaction is a type of chemical reaction in which a single compound breaks down into two or more simpler substances. The general form is AB \(\rightarrow\) A + B.

Step 2: Detailed Explanation:
Let's analyze the given reaction options: \[\begin{array}{rl} \bullet & \text{(A) \(H_2 + I_2 \rightarrow 2HI\): This is a combination reaction, where two reactants combine to form a single product.} \\ \bullet & \text{(B) \(NH_4CNO \rightarrow H_2NCONH_2\): This is a rearrangement or isomerization reaction, where the atoms of a single compound are rearranged to form a new compound.} \\ \bullet & \text{(C) \(NaOH + HCl \rightarrow NaCl + H_2O\): This is a neutralization reaction (a type of double displacement reaction), where an acid and a base react to form salt and water.} \\ \bullet & \text{(D) \(2KClO_3 \rightarrow 2KCl + 3O_2\): This is a decomposition reaction, where a single reactant, potassium chlorate (\(KClO_3\)), breaks down into two simpler products, potassium chloride (\(KCl\)) and oxygen (\(O_2\)).} \\ \end{array}\]

Step 3: Final Answer:
The reaction \(2KClO_3 \rightarrow 2KCl + 3O_2\) is an example of a decomposition reaction.