Question

1. in what kind of reaction do two or more substances combine to form a new compound?

a. decomposition reaction
b. ionic reaction
c. double-displacement reaction
d. synthesis reaction

Explanation:

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<reasoning>

Analyze the reaction definition

\[
\text{A} + \text{B}
ightarrow \text{AB}
\]

Evaluate the given options

• Decomposition: one reactant breaks down into multiple products.
• Double-displacement: two compounds exchange ions.
• Synthesis: two or more substances combine to form a single new compound.

</reasoning>

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

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Answer:

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<reasoning>

Analyze the reaction definition

\[
\text{A} + \text{B}
ightarrow \text{AB}
\]

Evaluate the given options

• Decomposition: one reactant breaks down into multiple products.
• Double-displacement: two compounds exchange ions.
• Synthesis: two or more substances combine to form a single new compound.

</reasoning>

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

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