The starting material used for the manufacture of `HNO_(3)` by Ostwald process is

Options

A. Ammonia and `N_(2)O`
B. Ammonia
C. Air only
D. Ammonia and nitrogen

Answer

To determine the starting material used for the manufacture of HNO₃ (nitric acid) by the Ostwald process, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Ostwald Process**: The Ostwald process is a method for producing nitric acid from ammonia. It involves several chemical reactions.

2. **Identify the Starting Material**: The primary starting material for the Ostwald process is ammonia (NH₃). This is the first reactant that is used in the process.

3. **Reaction with Oxygen**: In the presence of a catalyst (usually platinum), ammonia reacts with oxygen (O₂) to produce nitrogen monoxide (NO) and water (H₂O):
\[ 4 NH₃ + 5 O₂ \xrightarrow{Pt} 4 NO + 6 H₂O \]

4. **Formation of Nitrogen Dioxide**: The nitrogen monoxide (NO) produced then reacts with more oxygen to form nitrogen dioxide (NO₂):
\[ 2 NO + O₂ \rightarrow 2 NO₂ \]

5. **Production of Nitric Acid**: The nitrogen dioxide (NO₂) then reacts with water (H₂O) to produce nitric acid (HNO₃):
\[ 3 NO₂ + H₂O \rightarrow 2 HNO₃ + NO \]

6. **Conclusion**: From the above steps, it is clear that the starting material used for the manufacture of HNO₃ by the Ostwald process is ammonia (NH₃).

### Final Answer:
The starting material used for the manufacture of HNO₃ by the Ostwald process is **ammonia (NH₃)**.