Question

Which of the following are single-displacement reactions? Check all that apply.

A. Cl₂(g) + KBr(aq) → KCl(aq) + Br₂(l)
B. Mg(s) + 2H₂O(g) → Mg(OH)₂ + H₂(g)
C. AgNO₃(aq) + NaCl(aq) → AgCl(s) + NaNO₃(aq)
D. 2C₂H₆(g) + 7O₂(g) → 6H₂O(g) + 4CO₂(g)

Answer 1

Out of the given options, A and B are single-displacement reactions. Option A is the reaction of chlorine gas with aqueous potassium bromide, and option B is the reaction of magnesium solid with water vapor.

Step-by-step explanation:

To identify the single-displacement reactions from the provided options, we must recognize that a single-displacement reaction, also known as a single-replacement reaction, occurs when an element replaces another element in a compound. This process involves an element in either the solid, liquid, or gas state that is not an ion displacing another element from its compound.

• Option A. Cl₂(g) + KBr(aq) → KCl(aq) + Br₂(l) is a single-displacement reaction, where chlorine gas (Cl₂) displaces bromine (Br) in the compound KBr.
• Option B. Mg(s) + 2H₂O(g) → Mg(OH)₂ + H₂(g), though involving water, is a single-displacement reaction where solid magnesium (Mg) replaces hydrogen in water (H₂O).

Options C and D do not exhibit the characteristics of a single-displacement reaction. Option C is a double displacement reaction, and Option D represents a combustion reaction.