Question

Calculate the % of na in naoh

Answer 1

First, work out the relative formula mass of the compound, using the Ar values for each element. In the case of sodium hydroxide, these are Na = 23, O = 16, H = 1. (You will be given these numbers in the exam.)

Next, divide the Ar of oxygen by the Mr of NaOH, and multiply by 100 to get a percentage.