Question

1. when the following equation is balanced, what is the coefficient for \\(\text{hcl}\\)?

\\(\text{mg} + \text{hcl} \
ightarrow \text{mgcl}_2 + \text{h}_2\\)

a) 6

b) 3

c) 1

d) 2

Explanation:

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<reasoning>

Count atoms on both sides of the unbalanced equation

\[

$$\begin{aligned} &\text{Reactants:} \quad 1 \text{ Mg}, \quad 1 \text{ H}, \quad 1 \text{ Cl} \\ &\text{Products:} \quad 1 \text{ Mg}, \quad 2 \text{ H}, \quad 2 \text{ Cl} \end{aligned}$$

\]

Balance hydrogen and chlorine atoms

\[

$$\begin{aligned} &\text{Coefficient of } \text{HCl} = 2 \\ &\text{Balanced Equation:} \quad \text{Mg} + 2\text{HCl} ightarrow \text{MgCl}_2 + \text{H}_2 \end{aligned}$$

\]

Identify the coefficient for HCl

\[
\text{Coefficient} = 2
\]
</reasoning>

<answer>
<mcq-option>A) 6</mcq-option>
<mcq-option>B) 3</mcq-option>
<mcq-option>C) 1</mcq-option>
<mcq-correct>D) 2</mcq-correct>
</answer>

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Answer:

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<reasoning>

Count atoms on both sides of the unbalanced equation

\[

$$\begin{aligned} &\text{Reactants:} \quad 1 \text{ Mg}, \quad 1 \text{ H}, \quad 1 \text{ Cl} \\ &\text{Products:} \quad 1 \text{ Mg}, \quad 2 \text{ H}, \quad 2 \text{ Cl} \end{aligned}$$

\]

Balance hydrogen and chlorine atoms

\[

$$\begin{aligned} &\text{Coefficient of } \text{HCl} = 2 \\ &\text{Balanced Equation:} \quad \text{Mg} + 2\text{HCl} ightarrow \text{MgCl}_2 + \text{H}_2 \end{aligned}$$

\]

Identify the coefficient for HCl

\[
\text{Coefficient} = 2
\]
</reasoning>

<answer>
<mcq-option>A) 6</mcq-option>
<mcq-option>B) 3</mcq-option>
<mcq-option>C) 1</mcq-option>
<mcq-correct>D) 2</mcq-correct>
</answer>

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