Limiting reagent in a chemical reaction is that reactant which

Options

A. Left some amount unreacted after the completion of reaction
B. Reacts completely in the reaction
C. Does not react in the reaction
D. All of these

Answer

To determine the limiting reagent in a chemical reaction, we need to understand the definition and characteristics of a limiting reagent. Here’s a step-by-step solution to the question:

### Step 1: Understand the Concept of Limiting Reagent
The limiting reagent in a chemical reaction is the reactant that is completely consumed when the reaction goes to completion. This means that once this reactant is used up, the reaction cannot proceed any further, even if other reactants are still available.

### Step 2: Analyze the Statements
We need to evaluate the given statements to identify which one correctly describes the limiting reagent.

1. **Statement 1**: "Leaves some amount unreacted after the completion of reaction."
- This statement is incorrect because the limiting reagent is fully consumed.

2. **Statement 2**: "Reacts completely in a reaction."
- This statement is correct because the limiting reagent is the one that gets completely used up.

3. **Statement 3**: "Does not react in the reaction."
- This statement is incorrect because the limiting reagent is involved in the reaction until it is fully consumed.

4. **Statement 4**: "All of these."
- This statement is incorrect since not all the previous statements are true.

### Step 3: Identify the Correct Option
Based on the analysis, the correct statement about the limiting reagent is:
- **Correct Option**: "Reacts completely in a reaction."

### Conclusion
The limiting reagent in a chemical reaction is the reactant that is completely consumed when the reaction is completed.

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