A student prepares a solution by dissolving 5.65 g of KOH in enough water?

Question

to make 250. mL of solution.
The student then transfers 27.0 mL of this solution into a 100. mL volumetric flask. Water is then added
up to the 100. mL mark.
What is the final molarity of KOH in the 100. mL flask ?

Answer 1

the moles of KOH : 5.65/56 = 0.1
the molarity of the first solution : 0.1 / 0.25 = 0.4M
the moles of KOH in 27ml of this solution : 0.4 * 0.027 = 0.0108
the molarity of the final solution : 0.0108 / 0.1 = 0.108 M