Phosphorus occurs in nature in the form of stable phosphates. (Animal bones also contain calcuim phosphate (58%)).The important minerals are:
(i)Phosphorite, `Ca_3(PO_4)_2` (ii)Chloraptite,`Ca_3(PO_4)_2CaCl_2`
(iii)Fluoraptite, `Ca_3(PO_4)_2CaF_2`
There are some depoists of nitrates and phosphates in earth's crust.Nitrates are more soluble in water Nitrates are difficult to reduce under the laboratory conditions but microbes do it easily.Compounds of phosphorus and nitrogen are used as fertilizer.
Amongs the following which is not member of apatite family ?

Options

A. `Ca_9(PO_4)_6. CaCl_2`
B. `Ca_9(PO_4)_6.CaF_2`
C. `Ca_3(PO_4)_2.Ca(OH)_2`
D. None of these

Explanation

To solve the question about which compound is not a member of the apatite family, we will analyze the given minerals and their formulas step by step.

### Step 1: Understand the Apatite Family
The apatite family consists of minerals that share a similar structure and chemical formula. The general formula for apatite is represented as:
\[ \text{Ca}_9(\text{PO}_4)_6(\text{CaX}_2) \]
where \( X \) can be F (fluoride), Cl (chloride), or OH (hydroxide).

### Step 2: Analyze the Given Compounds
We have three compounds to analyze:
1. **Phosphorite**: \( \text{Ca}_3(\text{PO}_4)_2 \)
2. **Chlorapatite**: \( \text{Ca}_3(\text{PO}_4)_2 \cdot \text{CaCl}_2 \)
3. **Fluorapatite**: \( \text{Ca}_3(\text{PO}_4)_2 \cdot \text{CaF}_2 \)

### Step 3: Identify Each Compound
- **Chlorapatite**: This matches the apatite structure because it can be represented as \( \text{Ca}_9(\text{PO}_4)_6(\text{CaCl}_2) \).
- **Fluorapatite**: This also matches the apatite structure as it can be represented as \( \text{Ca}_9(\text{PO}_4)_6(\text{CaF}_2) \).
- **Phosphorite**: This does not match the apatite structure because it does not have the same formula as the apatite family.

### Step 4: Conclusion
Among the given options, **Phosphorite** is not a member of the apatite family.

### Final Answer
The compound that is not a member of the apatite family is **Phosphorite**.

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