Questions: Calculate the volume (in mL) of 0.100 M CaCl2 needed to produce 2.00 g of CaCO3(s). There is an excess of Na2CO3.
Molar mass of calcium carbonate = 100.09 g / mol
Transcript text: Calculate the volume (in mL ) of $0.100 \mathrm{M} \mathrm{CaCl}_{2}$ needed to produce 2.00 g of $\mathrm{CaCO}_{3}(\mathrm{~s})$. There is an excess of $\mathrm{Na}_{2} \mathrm{CO}_{3}$.
Molar mass of calcium carbonate $=100.09 \mathrm{~g} / \mathrm{mol}$
Solution
Solution Steps
Step 1: Determine Moles of \(\mathrm{CaCO}_3\)
First, calculate the number of moles of \(\mathrm{CaCO}_3\) using its given mass and molar mass.
\[
\text{Moles of } \mathrm{CaCO}_3 = \frac{\text{Mass of } \mathrm{CaCO}_3}{\text{Molar mass of } \mathrm{CaCO}_3} = \frac{2.00 \, \text{g}}{100.09 \, \text{g/mol}}
\]
\[
\text{Moles of } \mathrm{CaCO}_3 = 0.01998 \, \text{mol}
\]
Step 2: Use Stoichiometry to Find Moles of \(\mathrm{CaCl}_2\)
The balanced chemical equation for the reaction is:
From the equation, 1 mole of \(\mathrm{CaCl}_2\) produces 1 mole of \(\mathrm{CaCO}_3\). Therefore, the moles of \(\mathrm{CaCl}_2\) needed are equal to the moles of \(\mathrm{CaCO}_3\).
\[
\text{Moles of } \mathrm{CaCl}_2 = 0.01998 \, \text{mol}
\]
Step 3: Calculate Volume of \(\mathrm{CaCl}_2\) Solution
Use the molarity of the \(\mathrm{CaCl}_2\) solution to find the volume needed.
\[
\text{Molarity} = \frac{\text{Moles of solute}}{\text{Volume of solution in liters}}
\]
Rearranging for volume:
\[
\text{Volume of solution in liters} = \frac{\text{Moles of } \mathrm{CaCl}_2}{\text{Molarity}} = \frac{0.01998 \, \text{mol}}{0.100 \, \text{M}}
\]
\[
\text{Volume of solution in liters} = 0.1998 \, \text{L}
\]