What is the mole fraction of #KI# in a solution made by dissolving 3.4 g of #KI# in 5.8 g of water?

1 Answer
Jan 5, 2017

Answer:

#"Mole fraction"# #=# #"Moles of component"/"Moles of all species in solution"#

Explanation:

And thus, #"Mole fraction, KI"# #=# #"Moles of KI"/"Moles of KI + moles of water"#

#=((3.4*g)/(166.00*g*mol^-1))/((3.4*g)/(166.00*g*mol^-1)+(5.8*g)/(18.01*g*mol^-1))# #=# #0.060#

Note that the mole fraction of #"water"# here must be necessarily #1-0.060=0.94#. Why #"necessarily"#?

Note that #"mole fractions"#, as they are here, are dimensionless quantities.