The mole fraction of `CH_(3)OH` in an aqueous solution is 0.02 and its density is `0.994 g cm^(-3)`. Determine its molarity and molality.

Explanation

Let x mole of `CH_3OH` and y mole of water be present in solution
`"Mole fraction of "CH_3OH=x/(x+y)=0.02`
`"So, "y/x=49" or "x/y=1/49`
`"Molarity"=x/(18xxy)xx1000=1000/(18xx49)=1.13m`
`"Volume of solution"=("Total mass")/("density")`
`(32x xx18y)/0.994mL`
`(32x xx18y)/(0.994xx1000)litre=(23x xx18y)/994litre`
`"Molarity"=x/(32x+18y)`
`994/(32+18xxy//x)=994/(32+18xx49)=1.0875M`