Ammonia and oxygen combine to produce water vapour and nitric oxide as per the chemical equation: `4NH_(3)(g) + 5O_(2)(g) to 6H_(2)O(g) + 4NO`.
(iv) What is the volume of `NH_(3)` at STP that will combine with oxygen in reaction (ii)?

Explanation

To find the volume of ammonia (NH₃) at STP that will combine with oxygen (O₂) in the given reaction, we can follow these steps:

### Step 1: Understand the Reaction
The balanced chemical equation is:
\[ 4 \text{NH}_3(g) + 5 \text{O}_2(g) \rightarrow 6 \text{H}_2\text{O}(g) + 4 \text{NO}(g) \]

From this equation, we can see that 4 moles of ammonia react with 5 moles of oxygen.

### Step 2: Determine the Volume of Ammonia at STP
At standard temperature and pressure (STP), 1 mole of any gas occupies a volume of 22.4 liters.

### Step 3: Calculate the Volume of Ammonia
Since we need the volume of 4 moles of ammonia, we can use the relationship:
\[ \text{Volume} = \text{Number of moles} \times \text{Volume per mole at STP} \]

Substituting the values:
\[ \text{Volume of NH}_3 = 4 \text{ moles} \times 22.4 \text{ L/mole} \]

### Step 4: Perform the Calculation
Calculating the volume:
\[ \text{Volume of NH}_3 = 4 \times 22.4 = 89.6 \text{ liters} \]

### Conclusion
The volume of ammonia (NH₃) at STP that will combine with oxygen is **89.6 liters**.

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