WAEC - Chemistry (2011 - No. 31)
On evaporation to dryness, 250 cm3 of saturated solution of salt X with relative molar mass 101 gave 50.5g of the. What is the soluility of the salt?
1.0 mol dm-3
2.0 mol dm-3
4.0 moldm-3
5.0 moldm-3
Explicació
50.5g 0f salt X is contained in 250cm3,
what mass of X is contained in 1000cm3
= (50.5 x 1000) ÷ 250 = 202g
no of moles of salt x = mass÷ molar mass
= 202÷ 101 = 2.0mol/dm3