Which of the following is correct :

Options

A. `N_2 O` is a laughing gas and is angular in shape.
B. `NO_2` is a sweet smelling and is angular in shape.
C. `NO` is a colourless gas and acidic in nature.
D. `NO_2` on reaction with `NaOH` gives a mixture of two salts.

Explanation

To solve the question regarding which statement is correct, we will analyze each statement one by one.

### Step-by-Step Solution:

1. **Analyze Statement A: N2O is a laughing gas and is angular in shape.**
- N2O (nitrous oxide) is commonly known as laughing gas. However, its molecular geometry is linear, not angular. Therefore, this statement is **incorrect**.

2. **Analyze Statement B: NO2 is sweet smelling and is angular in shape.**
- NO2 (nitrogen dioxide) does have an angular shape due to the presence of a lone pair on the nitrogen atom. However, it is known for its pungent odor, not a sweet smell. Thus, this statement is also **incorrect**.

3. **Analyze Statement C: NO is colorless and has no effect on litmus.**
- NO (nitric oxide) is indeed a colorless gas. It is neutral and does not affect litmus paper, meaning it has no acidic or basic properties. However, since the question asks for correctness, we must note that while the first part is true, the phrasing could lead to confusion. Nevertheless, this statement is considered **incorrect** in the context of the question.

4. **Analyze Statement D: NO2 reacts with NaOH to give two salt mixtures.**
- The reaction of NO2 with NaOH does produce two salts: sodium nitrite (NaNO2) and sodium nitrate (NaNO3), along with water. The balanced equation for this reaction is:
\[ 2 NO2 + 2 NaOH \rightarrow NaNO2 + NaNO3 + H2O \]
- This statement is **correct**.

### Conclusion:
The correct statement among the options provided is **Statement D**.

---