How many moles of KI are required to produce 0.4 moles of `K_(2)HgI_(4)` ?

Options

A. 0.4
B. 0.8
C. 3.2
D. 1.6

Explanation

To determine how many moles of KI are required to produce 0.4 moles of K2HgI4, we first need to understand the balanced chemical reaction involved in the formation of K2HgI4.

### Step 1: Write the balanced chemical equation
The reaction for the formation of K2HgI4 from KI and HgI2 can be represented as:
\[ 2 \text{KI} + \text{HgI}_2 \rightarrow \text{K}_2\text{HgI}_4 \]

### Step 2: Analyze the stoichiometry of the reaction
From the balanced equation, we can see that:
- 2 moles of KI are required to produce 1 mole of K2HgI4.

### Step 3: Calculate the moles of KI required for 0.4 moles of K2HgI4
To find out how many moles of KI are needed to produce 0.4 moles of K2HgI4, we can set up a proportion based on the stoichiometry:
- If 1 mole of K2HgI4 requires 2 moles of KI, then 0.4 moles of K2HgI4 will require:
\[ \text{Moles of KI} = 0.4 \text{ moles K2HgI4} \times \frac{2 \text{ moles KI}}{1 \text{ mole K2HgI4}} = 0.8 \text{ moles KI} \]

### Final Answer
Thus, to produce 0.4 moles of K2HgI4, **0.8 moles of KI are required**.

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