Question 3

Single replacement reactions are exemplified by the given equation.

The chemical equation Cr + Fe(NO₃)₂ → Fe + Cr(NO₃)₂ illustrates a single replacement reaction, where chromium replaces iron in the compound.

A) Single replacement

This option is correct because the reaction involves one element (chromium) displacing another element (iron) from its compound (iron(II) nitrate). This is the defining characteristic of a single replacement reaction.

B) Decomposition

Decomposition reactions involve a single compound breaking down into two or more simpler substances. This option is incorrect, as the provided equation shows an element replacing another in a compound, not a breakdown of a single compound.

C) Double replacement

In double replacement reactions, two compounds exchange their components to form two new compounds. This option is incorrect because the equation shows only one compound being affected, not two exchanging their parts.

D) Combustion

Combustion reactions typically involve a substance reacting with oxygen to produce energy, usually in the form of heat and light. This option is incorrect as the equation does not represent a reaction with oxygen or the characteristics of a combustion reaction.

Conclusion

The correct answer is A) Single replacement, as the reaction clearly demonstrates one element displacing another from a compound. The other options are incorrect as they describe different types of reactions that do not apply to the context of the provided chemical equation. Thus, the nature of the reaction aligns precisely with the definition of a single replacement reaction.