The mixed anhydride of nitrous and nitric acid is.

Options

A. `N_2 O`
B. `NO_2`
C. `NO`
D. `N_2 O_5`

Explanation

To solve the question regarding the mixed anhydride of nitrous and nitric acid, we can follow these steps:

### Step 1: Understand the Concept of Mixed Anhydrides
Mixed anhydrides are compounds formed from two different acids that can react with water to produce the corresponding acids. In this case, we are looking for the mixed anhydride of nitrous acid (HNO2) and nitric acid (HNO3).

**Hint:** Recall that an anhydride is typically formed from the removal of water from an acid.

### Step 2: Identify the Acids Involved
The acids we are dealing with are:
- Nitrous acid (HNO2)
- Nitric acid (HNO3)

**Hint:** Write down the chemical formulas of the acids to visualize what you are working with.

### Step 3: Determine the Mixed Anhydride
The mixed anhydride of nitrous acid and nitric acid can be represented as NO2. This compound can react with water to yield both HNO2 and HNO3.

**Hint:** Consider the reaction that occurs when the anhydride is mixed with water.

### Step 4: Write the Reaction
The balanced chemical equation for the reaction of the mixed anhydride with water is:
\[ \text{NO}_2 + \text{H}_2\text{O} \rightarrow \text{HNO}_3 + \text{HNO}_2 \]

**Hint:** Ensure that the equation is balanced in terms of both mass and charge.

### Step 5: Conclusion
Thus, the mixed anhydride of nitrous acid and nitric acid is NO2.

**Final Answer:** The mixed anhydride of nitrous and nitric acid is NO2.

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