The question requires us to calculate the number of moles of NaCl in 1.66 L of a 0.400 M NaCl solution.
To answer this question, we need to keep in mind that the molar concentration provides the amount of moles in one liter solution. Thus, we can write that:
1 L of NaCl solution -------------- 0.400 mol of NaCl
We can use this information to calculate the amount of NaCl, in moles, in 1.66 L in a 0.400 M NaCl solution:
1 L of NaCl solution -------------- 0.400 mol of NaCl
1.66 L of NaCl solution --------- x
Solving for x, we have:
Therefore, there are 0.664 moles of NaCl in 1.66 L of a 0.400 M NaCl solution.