The percentage composition (by weight) of a solution is 45%X, 15%Y,and 40% Z. Calculate the mole fraction of Z component of the solution.(Molecular mass of X = 18,Y=60 and Z = 60)

Options

A. `0.87`
B. `0.197`
C. `0.259`
D. `0.216`

Answer

B

Explanation

NO. of moles of `X = 45 % , n _(1) = ( 45)/(18) = 2. 5`
`Y = 15%, n _(2) = (15)/(60) = 0. 25 ," " Z = 40 % , n _(3) = ( 40)/(60) = 0. 666`
`X _(1) = ( n _(1))/( n _(1) + n _(2) + n _(3)) = ( 2. 5)/( 2. 5 + 0. 25 + 0. 666 ) = ( 2. 5)/( 3.416 ) = 0. 73`
`X _(3) = (n _(3))/( n _(1) + n _(2) + n _(3)) = ( 0. 25)/( 3. 416) = 0.073`
`X _(3) = [ 1- ( X _(1) + X _(2)) ] = ( 1- 0.73 - 0.073) = 0.197`