In the ostwald's process, nitric acid is prepared by the catalytic oxidation of :

Options

A. `N_(2)`
B. `NH_(3)`
C. `N_(2)O_(5)`
D. `NO_(2)`

Explanation

To solve the question regarding the Ostwald process for the preparation of nitric acid, we can break it down into several steps:

### Step 1: Identify the Starting Material
In the Ostwald process, the starting material is ammonia (NH₃).

**Hint:** Remember that the Ostwald process specifically uses ammonia as the primary reactant.

### Step 2: Catalytic Oxidation of Ammonia
Ammonia is oxidized in the presence of oxygen (O₂) using a catalyst (usually platinum or rhodium). The reaction can be represented as:
\[ 4 NH₃ + 5 O₂ \rightarrow 4 NO + 6 H₂O \]

**Hint:** Catalytic oxidation involves a catalyst that facilitates the reaction without being consumed.

### Step 3: Formation of Nitrogen Dioxide
The nitrogen monoxide (NO) produced in the first step is then further oxidized. The reaction is:
\[ 2 NO + O₂ \rightarrow 2 NO₂ \]

**Hint:** This step involves the oxidation of NO to NO₂, which is a crucial intermediate in the process.

### Step 4: Reaction with Water
The nitrogen dioxide (NO₂) produced reacts with water (H₂O) to form nitric acid (HNO₃) and nitrogen monoxide (NO):
\[ 3 NO₂ + H₂O \rightarrow 2 HNO₃ + NO \]

**Hint:** This step shows how NO₂ is converted into nitric acid while recycling some NO back into the process.

### Step 5: Overall Reaction
Combining all the steps, the overall reaction for the Ostwald process can be summarized as:
\[ 4 NH₃ + 7 O₂ \rightarrow 4 HNO₃ + 2 NO + 2 H₂O \]

**Hint:** The overall reaction gives you a complete picture of how ammonia is transformed into nitric acid through a series of reactions.

### Conclusion
In conclusion, in the Ostwald process, nitric acid (HNO₃) is prepared by the catalytic oxidation of ammonia (NH₃).

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