Which reaction involves one element replacing a similar element in a compound?

Which reaction involves one element replacing a similar element in a compound?

• A. Combination reaction
• B. Displacement reaction
• C. Decomposition reaction
• D. Neutralization reaction

Answer: (B)

This question tests understanding of displacement reactions, where a more reactive element pushes a less reactive element out of a compound. In such a reaction, the free element donates electrons and takes the place of the other element in the compound, forming a new compound with the remaining part and releasing the displaced element as a metal (or another element) free. An example helps: zinc metal reacting with copper sulfate solution produces zinc sulfate and copper metal. Here, zinc, being more reactive, displaces copper from the copper sulfate, so copper metal plates out and zinc sulfate forms. The driving idea is the reactivity series: elements higher up are more able to undergo oxidation and push out those below them in a compound. Other reaction types don’t involve replacing an element inside a compound. A combination reaction simply forms one product from two or more reactants. A decomposition reaction breaks a compound into simpler substances. A neutralization reaction is an acid reacting with a base to make a salt and water.

This question tests understanding of displacement reactions, where a more reactive element pushes a less reactive element out of a compound. In such a reaction, the free element donates electrons and takes the place of the other element in the compound, forming a new compound with the remaining part and releasing the displaced element as a metal (or another element) free.

An example helps: zinc metal reacting with copper sulfate solution produces zinc sulfate and copper metal. Here, zinc, being more reactive, displaces copper from the copper sulfate, so copper metal plates out and zinc sulfate forms. The driving idea is the reactivity series: elements higher up are more able to undergo oxidation and push out those below them in a compound.

Other reaction types don’t involve replacing an element inside a compound. A combination reaction simply forms one product from two or more reactants. A decomposition reaction breaks a compound into simpler substances. A neutralization reaction is an acid reacting with a base to make a salt and water.