To determine how many moles of CaCl2 are required to prepare 2.00 liters of a 0.804 molar (M) CaCl2 solution, follow these steps:
1. Understand the concept of molarity (M):
Molarity is defined as the number of moles of solute (in this case, CaCl2) per liter of solution. It is given by the formula:
[tex]\[
\text{Molarity (M)} = \frac{\text{moles of solute}}{\text{volume of solution in liters}}
\][/tex]
2. Rearrange the formula to solve for moles of solute:
[tex]\[
\text{moles of solute} = \text{Molarity (M)} \times \text{volume of solution in liters}
\][/tex]
3. Substitute the given values into the formula:
Given:
- Volume of the solution (V) = 2.00 liters
- Molarity (M) = 0.804 M
Hence,
[tex]\[
\text{moles of CaCl2} = 0.804 \, \text{M} \times 2.00 \, \text{L}
\][/tex]
4. Perform the multiplication:
[tex]\[
\text{moles of CaCl2} = 1.608
\][/tex]
5. Round the result to two decimal places:
[tex]\[
\text{moles of CaCl2} \approx 1.61
\][/tex]
Therefore, 1.61 moles of CaCl2 are required to prepare 2.00 liters of a 0.804 molar CaCl2 solution.