A sample of ammonium phosphate ,`(NH_(4))_(3) PO_(4)` , contains 6 moles of hydrogen atom , The no. of moles of oxygen atom are:

Options

A. 1
B. 2
C. 4
D. 6

Answer

To solve the problem, we need to determine the number of moles of oxygen atoms in ammonium phosphate, given that the sample contains 6 moles of hydrogen atoms.

### Step-by-Step Solution:

1. **Identify the Chemical Formula**:
The chemical formula for ammonium phosphate is \((NH_4)_3PO_4\).

2. **Determine the Number of Hydrogen Atoms in One Mole of Ammonium Phosphate**:
Each ammonium ion \((NH_4)^+\) contains 4 hydrogen atoms. Since there are 3 ammonium ions in ammonium phosphate:
\[ \text{Total moles of hydrogen in 1 mole of } (NH_4)_3PO_4 = 3 \times 4 = 12 \text{ moles of hydrogen} \]

3. **Relate the Given Moles of Hydrogen to Moles of Ammonium Phosphate**:
We are given that there are 6 moles of hydrogen atoms in the sample. To find out how many moles of ammonium phosphate this corresponds to, we set up the following proportion:
\[ \text{If 1 mole of } (NH_4)_3PO_4 \text{ has 12 moles of hydrogen, then } x \text{ moles of } (NH_4)_3PO_4 \text{ will have 6 moles of hydrogen.} \]
\[ x \times 12 = 6 \implies x = \frac{6}{12} = \frac{1}{2} \text{ moles of } (NH_4)_3PO_4 \]

4. **Determine the Number of Moles of Oxygen Atoms in Half a Mole of Ammonium Phosphate**:
The formula \((NH_4)_3PO_4\) indicates that there is 1 phosphate group, which contains 4 oxygen atoms. Therefore, in 1 mole of ammonium phosphate, there are 4 moles of oxygen atoms. For half a mole of ammonium phosphate:
\[ \text{Moles of oxygen} = 4 \times \frac{1}{2} = 2 \text{ moles of oxygen} \]

5. **Conclusion**:
The number of moles of oxygen atoms in the sample is 2 moles.

### Final Answer:
The number of moles of oxygen atoms in the sample of ammonium phosphate is **2 moles**.

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