Question

the reaction represented by the equation \\(\text{mg(s)} + 2\text{hcl(aq)} \
ightarrow \text{h}_2\text{(g)} + \text{mgcl}_2\text{(aq)}\\) is a

a. composition reaction.
b. decomposition reaction.
c. single-displacement reaction.
d. double-displacement reaction.

Explanation:

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<reasoning>

Analyze the chemical equation structure

\[
\text{Mg}(s) + 2\text{HCl}(aq)
ightarrow \text{H}_2(g) + \text{MgCl}_2(aq)
\]
This reaction follows the general form:
\[
\text{A} + \text{BC}
ightarrow \text{B} + \text{AC}
\]

Identify the reaction type

The free element magnesium (\(\text{Mg}\)) replaces the hydrogen (\(\text{H}\)) in hydrochloric acid (\(\text{HCl}\)), releasing hydrogen gas and forming magnesium chloride. This represents a single-displacement (or single-replacement) reaction.
</reasoning>

<answer>
<mcq-option>a. composition reaction.</mcq-option>
<mcq-option>b. decomposition reaction.</mcq-option>
<mcq-correct>c. single-displacement reaction.</mcq-correct>
<mcq-option>d. double-displacement reaction.</mcq-option>
</answer>

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Answer:

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<reasoning>

Analyze the chemical equation structure

\[
\text{Mg}(s) + 2\text{HCl}(aq)
ightarrow \text{H}_2(g) + \text{MgCl}_2(aq)
\]
This reaction follows the general form:
\[
\text{A} + \text{BC}
ightarrow \text{B} + \text{AC}
\]

Identify the reaction type

The free element magnesium (\(\text{Mg}\)) replaces the hydrogen (\(\text{H}\)) in hydrochloric acid (\(\text{HCl}\)), releasing hydrogen gas and forming magnesium chloride. This represents a single-displacement (or single-replacement) reaction.
</reasoning>

<answer>
<mcq-option>a. composition reaction.</mcq-option>
<mcq-option>b. decomposition reaction.</mcq-option>
<mcq-correct>c. single-displacement reaction.</mcq-correct>
<mcq-option>d. double-displacement reaction.</mcq-option>
</answer>

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