What is the mole fraction of #KCl# in a mixture of 0.564g #NaCl#, 1.52g #KCl# and 0.857g #LiCl#?

1 Answer
Dec 23, 2016

#"Mole fraction of KCl"# #=# #0.402#

Explanation:

#"Mole fraction of component"# #=# #"Moles of component"/"Moles of all components"#

#"Moles of KCl"=(1.52*g)/(74.55*g*mol^-1)# #=# #0.0204*mol#

#"Moles of NaCl"=(0.564*g)/(58.44*g*mol^-1)# #=# #9.65xx10^-3*mol#

#"Moles of LiCl"=(0.857*g)/(42.39*g*mol^-1)# #=# #0.0202*mol#

#"Mole fraction of KCl"=(0.0204*mol)/((0.0202+0.00965+0.0204)*mol)#

#=# #0.402#

Just as a check, the sum of the mole fractions of all the components should give unity.

#"Mole fraction of NaCl"=(9.65xx10^-3*mol)/((0.0202+0.00965+0.0204)*mol)#

#=# #0.192#

#"Mole fraction of LiCl"=(0.0202*mol)/((0.0202+0.00965+0.0204)*mol)#

#=# #0.402#

The sum of the mole fractions do give unity as required.