Calculate the number of moles of methanol in 5 litres of its 2 m solution if the density of solution is 0.981 kg`L^(-1)` (Molar mass of methanol=32.0g `mol^(-1)`.

Explanation

Mass of 5L solution ` = 5L xx 0.981 kg L^(-1)`
` = 4.905 kg = 4905 g`
Mass of 2 m solution = 1000 g + 2 moles of methanol .
` = 1000 + 2 xx 32`
`= 1000 + 64 = 1064 g`
Now 1064 g of solution contians methanol = 2 mol 4905 g of solution contains methanol ` =(2)/(1064) xx 4905`
` = 9.22` mol.