Not incorrect among the following

Options

A. `N_(2)&H_(2)` are two non-reacting gases
B. `O_(2)&H_(2)` are two non-reacting gases
C. `N_(2)&D_(2)` are reactive towards each other
D. `D_(2)&O_(2)` are non-reactive to each other

Answer

To solve the question "Not incorrect among the following," we need to evaluate each statement provided and identify which one is correct.

### Step-by-Step Solution:

1. **Evaluate Statement 1: N2 and H2 are two non-reactive gases.**
- **Analysis:** Nitrogen (N2) and hydrogen (H2) can react to form ammonia (NH3) through the Haber process. The balanced equation for this reaction is:
\[ N_2 + 3H_2 \rightarrow 2NH_3 \]
- **Conclusion:** This statement is incorrect because N2 and H2 are reactive.

2. **Evaluate Statement 2: O2 and H2 are two non-reactive gases.**
- **Analysis:** Oxygen (O2) and hydrogen (H2) react to form water (H2O). The balanced equation for this reaction is:
\[ 2H_2 + O_2 \rightarrow 2H_2O \]
- **Conclusion:** This statement is also incorrect because O2 and H2 are reactive.

3. **Evaluate Statement 3: N2 and D2 are reactive towards each other.**
- **Analysis:** Nitrogen (N2) can react with deuterium (D2) to form deuterated ammonia (ND3). The balanced equation for this reaction is:
\[ N_2 + 3D_2 \rightarrow 2ND_3 \]
- **Conclusion:** This statement is correct because N2 and D2 do react with each other.

4. **Evaluate Statement 4: D2 and O2 are non-reactive to each other.**
- **Analysis:** Deuterium (D2) and oxygen (O2) can react to form heavy water (D2O). The balanced equation for this reaction is:
\[ 2D_2 + O_2 \rightarrow 2D_2O \]
- **Conclusion:** This statement is incorrect because D2 and O2 are reactive.

### Final Answer:
The only correct statement among the provided options is **Statement 3: N2 and D2 are reactive towards each other.**

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