The catalyst used in the manufacture of `NO` by Ostwald's process is

Options

A. Pt
B. Fe
C. Mo
D. Cu

Answer

To solve the question regarding the catalyst used in the manufacture of nitrogen monoxide (NO) by the Ostwald process, we can follow these steps:

### Step 1: Understand the Ostwald Process
The Ostwald process is primarily used for the production of nitric acid (HNO3). The first step in this process involves the oxidation of ammonia (NH3) to produce nitrogen monoxide (NO).

**Hint:** Familiarize yourself with the Ostwald process and its significance in nitric acid production.

### Step 2: Identify the Reaction
The reaction for the production of nitrogen monoxide from ammonia can be represented as:
\[ 4 NH_3(g) + 5 O_2(g) \rightarrow 4 NO(g) + 6 H_2O(g) \]
This reaction requires a catalyst to proceed efficiently.

**Hint:** Recall the chemical equation involved in the Ostwald process and the reactants used.

### Step 3: Determine the Catalyst
In the Ostwald process, the catalyst used for the oxidation of ammonia to nitrogen monoxide is platinum (Pt). Platinum is known for its catalytic properties, particularly in high-temperature reactions.

**Hint:** Consider the properties of catalysts and why platinum is chosen for this specific reaction.

### Step 4: Note the Conditions
The reaction typically occurs under specific conditions: a pressure of about 5 atm and a temperature of approximately 850 degrees Celsius. These conditions help facilitate the reaction while using the catalyst effectively.

**Hint:** Remember the conditions under which the Ostwald process operates, as they are crucial for the reaction's success.

### Conclusion
The catalyst used in the manufacture of nitrogen monoxide by the Ostwald process is platinum (Pt).

**Final Answer:** Platinum (Pt)

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