Question

Calculate the weight of naoh present in 500 ml of 0.5 n solution

Answer 1

Normality = number of hydroxide ions in Sodium hydroxide × molarity of Sodium hydroxide.

There is only 1 hydroxide ion in Sodium hydroxide.

Molarity is thus :

0.5 / 1 = 0.5 M

Moles in 500ml is :

500/1000 × 0.5 = 0.25 moles

Moles = mass / molar mass

Molar mass of NaOH = 23 + 16 + 1 = 40

Mass = 40 × 0.25 = 10g