Question

How many moles of KOH is present in 30cm3 of 0.2M .Find the molarity of solution ?​

Answer 1

Volume of solution = 30 cm3 => 0.03 L of KOH solution.

Molarity = 0.2 M

Molarity = (no. of moles)/(litres of solution)

0.2 = (no. of moles)/(0.03)

=> no. of moles of KOH = 0.03 x 0.2 => 0.006 moles of KOH is present.

Normality = Molarity x N-Factor

N-Factor = 1 for KOH ( 1 OH-1 ion per molecule on complete dissociation in aqueous state)

Normality = 0.2 x 1

Normality = 0.2 N

Answer 2

Solution:

Given

Molarity = 0.2M

Volume = 30cm3

= 0.03 L (1L = 1000cm3) Molarity = No. of moles/Volume of solution

No. of moles = Molarity x volume of solution

= 0.2 x 0.03 mol

= 0.006 mol