The precentage composition of calcium , carbon and oxygen in `C_(a) CO_(3)` respectively are

Options

A. 40% , 12% and 48%
B. 12% , 40% and 48%
C. 40% , 48% and 12%
D. 12% , 48% and 40%

Answer

To find the percentage composition of calcium (Ca), carbon (C), and oxygen (O) in calcium carbonate (CaCO₃), we will follow these steps:

### Step 1: Determine the molar mass of calcium carbonate (CaCO₃)

1. **Identify the atomic masses**:
- Atomic mass of Calcium (Ca) = 40 g/mol
- Atomic mass of Carbon (C) = 12 g/mol
- Atomic mass of Oxygen (O) = 16 g/mol

2. **Calculate the total molar mass of CaCO₃**:
- CaCO₃ contains:
- 1 atom of Calcium = 40 g/mol
- 1 atom of Carbon = 12 g/mol
- 3 atoms of Oxygen = 3 × 16 g/mol = 48 g/mol
- Total molar mass of CaCO₃ = 40 + 12 + 48 = 100 g/mol

### Step 2: Calculate the percentage composition of each element

1. **Percentage of Calcium (Ca)**:
\[ \text{Percentage of Ca} = \left( \frac{\text{mass of Ca}}{\text{molar mass of CaCO}_3} \right) \times 100 = \left( \frac{40 \text{ g}}{100 \text{ g}} \right) \times 100 = 40\% \]

2. **Percentage of Carbon (C)**:
\[ \text{Percentage of C} = \left( \frac{\text{mass of C}}{\text{molar mass of CaCO}_3} \right) \times 100 = \left( \frac{12 \text{ g}}{100 \text{ g}} \right) \times 100 = 12\% \]

3. **Percentage of Oxygen (O)**:
\[ \text{Percentage of O} = \left( \frac{\text{mass of O}}{\text{molar mass of CaCO}_3} \right) \times 100 = \left( \frac{48 \text{ g}}{100 \text{ g}} \right) \times 100 = 48\% \]

### Final Result

The percentage composition of calcium, carbon, and oxygen in calcium carbonate (CaCO₃) is:
- Calcium (Ca): 40%
- Carbon (C): 12%
- Oxygen (O): 48%

### Answer
The correct option is A: 40%, 12%, and 48%.

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