WAEC - Chemistry (2001 - No. 46)

Calculate the mass of sodium hydroxide in 5.00 dm3 of a 0.125 mol dm-3 solution [NaOH = 40 g mol]

0.0156 g

0.625 g

1.00 g

25. 0 g

1 mole of NaOH per dm3 has a mass of 40g mass of NaOH in 0.125 mole = 0.125 x 40 = 5g mass in 5.00 dm3 of the solution = 5 x 5 = 25.0g