Which of the following salt are insoluble in water ?

Options

A. chlorides of fe and Mn
B. Nitrates of Ag and Pb
C. carbonates of Pb and Cu
D. phosphates of Na and `NH_(4)`

Explanation

To determine which salts are insoluble in water, we can follow these steps:

### Step 1: Understand Solubility Rules
Solubility rules help us predict whether a salt will dissolve in water. Generally, certain types of salts are known to be soluble or insoluble based on their composition.

### Step 2: Identify Common Soluble Salts
1. **Nitrates (NO3-)**: All nitrates are soluble in water.
2. **Group 1 Salts**: Salts containing alkali metals (Li+, Na+, K+, Rb+, Cs+) are soluble.
3. **Most Sulfates (SO4^2-)**: Most sulfates are soluble, with exceptions like barium sulfate (BaSO4) and lead(II) sulfate (PbSO4).

### Step 3: Identify Common Insoluble Salts
1. **Carbonates (CO3^2-)**: Most carbonates are insoluble, except those of alkali metals and ammonium.
2. **Phosphates (PO4^3-)**: Most phosphates are insoluble, except those of alkali metals and ammonium.
3. **Silver Salts**: Most silver salts (like AgCl, AgBr) are insoluble.
4. **Barium Sulfate (BaSO4)** and **Lead(II) Sulfate (PbSO4)**: These sulfates are exceptions and are insoluble.

### Step 4: Analyze the Given Salts
If a list of salts is provided, we can apply the solubility rules to each salt to determine which are insoluble. For example:
- **AgCl**: Insoluble (silver salt)
- **BaSO4**: Insoluble (exception of sulfates)
- **Na2CO3**: Soluble (contains Na+, a group 1 metal)
- **Ca3(PO4)2**: Insoluble (phosphate)

### Conclusion
By applying these solubility rules, we can identify which salts from the provided options are insoluble in water.

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