To determine the number of moles of KI in 125 mL of 0.20 M KI, we proceed as follows:
1. Convert the volume from milliliters to liters:
We are given 125 mL of KI solution. Since there are 1000 mL in a liter, we convert milliliters to liters:
[tex]\[
125 \, \text{mL} = \frac{125}{1000} \, \text{L} = 0.125 \, \text{L}
\][/tex]
2. Use the molarity to find the moles of KI:
Molarity (M) is defined as the number of moles of solute per liter of solution. Given that the concentration of the KI solution is 0.20 M, we can calculate the moles of KI (n) as follows:
[tex]\[
\text{Molarity} = \frac{\text{moles of solute}}{\text{volume of solution in liters}}
\][/tex]
Therefore,
[tex]\[
\text{moles of KI} = \text{Molarity} \times \text{Volume in liters}
\][/tex]
Substituting the known values:
[tex]\[
\text{moles of KI} = 0.20 \, \text{M} \times 0.125 \, \text{L} = 0.025 \, \text{mol}
\][/tex]
Thus, the number of moles of KI present in 125 mL of 0.20 M KI is:
[tex]\[
0.025 \, \text{mol}
\][/tex]
