`Ca_(3)(PO_(4))_(2)` is :

Options

A. Thomos slag
B. Used in cement manufacturing
C. Used in manufacture of phosphorus fertiliser
D. Used as a refractory meterial

Answer

To determine the classification of the compound \( Ca_3(PO_4)_2 \), we can follow these steps:

### Step 1: Identify the Components
The compound \( Ca_3(PO_4)_2 \) consists of calcium ions (Ca) and phosphate ions (PO₄).

**Hint:** Look for the elements and their common ions in the periodic table.

### Step 2: Determine the Nature of Calcium
Calcium (Ca) is an alkaline earth metal, which is found in Group 2 of the periodic table. Alkaline earth metals typically have a +2 oxidation state.

**Hint:** Recall the group classification of metals in the periodic table to identify alkaline earth metals.

### Step 3: Analyze the Phosphate Ion
The phosphate ion (PO₄) has a charge of -3. In the compound \( Ca_3(PO_4)_2 \), there are two phosphate ions, contributing a total charge of -6.

**Hint:** Remember the common charges of polyatomic ions like phosphate.

### Step 4: Balance the Charges
To balance the -6 charge from the two phosphate ions, we need three calcium ions, each with a +2 charge, contributing a total of +6 charge. This confirms that the compound is electrically neutral.

**Hint:** Check if the total positive charge equals the total negative charge for neutrality.

### Step 5: Classify the Compound
Since the compound is made up of a metal (calcium) and a polyatomic ion (phosphate), it is classified as an ionic compound.

**Hint:** Identify the type of bonding based on the nature of the elements involved.

### Step 6: Identify Uses
Calcium phosphate is commonly used in various applications, including the manufacture of cement and as a phosphorus fertilizer.

**Hint:** Consider the practical applications of compounds in chemistry.

### Conclusion
Thus, \( Ca_3(PO_4)_2 \) is classified as an ionic compound, specifically calcium phosphate.

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