A chemical reaction : `A + BrarrAB` , B is acting as limiting reagent then choose the correct option. The limiting reagent is
`{:(" A"," B "),("(1) 50 atom ","100 atom "),("(2) 100 atom ","200 atom "),("(3) 50 atom ","30 atom "),("(4) 50 atom ","200 atom "):}`

Options

A. a. 1
B. b. 2
C. c. 3
D. d. 4

Answer

To solve the problem, we need to identify the limiting reagent in the given chemical reaction:

**Reaction:** A + B → AB

**Given:** B is acting as the limiting reagent.

### Step-by-Step Solution:

1. **Understanding Limiting Reagent:**
- A limiting reagent is the reactant that is completely consumed in a chemical reaction, determining the maximum amount of product that can be formed.

2. **Analyzing the Options:**
- We have four pairs of quantities for A and B:
1. (50 ATM, 100 ATM)
2. (100 ATM, 200 ATM)
3. (50 ATM, 30 ATM)
4. (50 ATM, 200 ATM)

3. **Identifying the Limiting Reagent:**
- Since it is given that B is the limiting reagent, we need to find the pair where B has a smaller quantity compared to A.
- Let's evaluate each option:
- **Option 1:** A = 50 ATM, B = 100 ATM → B is in excess (not limiting).
- **Option 2:** A = 100 ATM, B = 200 ATM → B is in excess (not limiting).
- **Option 3:** A = 50 ATM, B = 30 ATM → B is in less quantity (limiting).
- **Option 4:** A = 50 ATM, B = 200 ATM → B is in excess (not limiting).

4. **Conclusion:**
- The only option where B is in less quantity than A is **Option 3: (50 ATM, 30 ATM)**. Therefore, this is the correct answer.

### Final Answer:
The correct option is **(3) 50 ATM, 30 ATM**.

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