In the equation `NaOH + HNO_3 to NaNO_3 +H_2O` nitric acid is acting as

Options

A. an oxidising agent
B. an acid
C. a nitrating agent
D. a dehydrating agent

Explanation

To determine how nitric acid (HNO₃) is acting in the reaction `NaOH + HNO₃ → NaNO₃ + H₂O`, we can follow these steps:

### Step 1: Identify the Reactants and Products
In the given reaction, we have two reactants: sodium hydroxide (NaOH) and nitric acid (HNO₃). The products of the reaction are sodium nitrate (NaNO₃) and water (H₂O).

### Step 2: Understand the Role of Nitric Acid
Nitric acid is a strong acid. In this reaction, it donates a proton (H⁺) to sodium hydroxide (NaOH), which is a base. This proton transfer is characteristic of acid-base reactions.

### Step 3: Analyze the Reaction Type
The reaction between NaOH and HNO₃ is a neutralization reaction. In this type of reaction, an acid reacts with a base to produce a salt (in this case, sodium nitrate) and water.

### Step 4: Determine the Specific Role of HNO₃
In addition to being an acid, nitric acid can also introduce a nitrate group (NO₃) into a compound. In this reaction, it replaces the hydroxide (OH) group from NaOH with the nitrate (NO₃) group, leading to the formation of sodium nitrate (NaNO₃).

### Step 5: Conclude the Role of Nitric Acid
Since HNO₃ is causing the introduction of the nitrate group into the product, it is acting as a nitrating agent in this reaction.

### Final Answer
In the equation `NaOH + HNO₃ → NaNO₃ + H₂O`, nitric acid (HNO₃) is acting as a nitrating agent.

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