Question

What is the molecular weight of \( \text{CaCO}_3 \)?

• A. \( 100 \, \text{g/mol} \)
• B. \( 150 \, \text{g/mol} \)
• C. \( 120 \, \text{g/mol} \)
• D. \( 200 \, \text{g/mol} \)

Hint:

To calculate the molecular weight of a compound, sum the atomic masses of all the atoms in its formula.

Answer 1

The Correct Option is A

Step 1: Understand the given data. We are asked to find the molecular weight of calcium carbonate, \( \text{CaCO}_3 \). Step 2: Calculate the molar mass of \( \text{CaCO}_3 \). To find the molecular weight of \( \text{CaCO}_3 \), we sum the atomic masses of all the atoms in the formula. - Calcium (Ca) has an atomic mass of \( 40.1 \, \text{g/mol} \). - Carbon (C) has an atomic mass of \( 12.0 \, \text{g/mol} \). - Oxygen (O) has an atomic mass of \( 16.0 \, \text{g/mol} \), and there are 3 oxygen atoms in \( \text{CaCO}_3 \). So, the molecular weight is: \[ \text{Molar mass of CaCO}_3 = 40.1 + 12.0 + (3 \times 16.0) = 40.1 + 12.0 + 48.0 = 100.1 \, \text{g/mol} \] Answer: Therefore, the molecular weight of \( \text{CaCO}_3 \) is approximately \( 100 \, \text{g/mol} \).