Question

Pleaseeee help I’m stuck on this problem

What is the mole fraction of KCI in a
mixture of 0.564 g NaCl, 1.52 g KCI,
and 0.857 g LICI?

Answer 1

.4

Step-by-step explanation:

Answer 2

0.4

Step-by-step explanation:

Given parameters:

Mass of NaCl = 0.564g

Mass of KCl = 1.52g

Mass of LiCl = 0.857g

Unknown:

Mole fraction of KCl = ?

Solution:

First, find the number of moles of the given species;

Number of moles =
`(mass)/(molar mass)`

Molar mass of KCl = 39 + 35.5 = 74.5g/mol

Molar mass of NaCl = 23 + 35.5 = 58.5g/mol

Molar mass of LiCl = 7 + 35.5 = 42.5g/mol

Number of moles of KCl =
`(1.52)/(74.5)` = 0.02mol

Number of moles of NaCl =
`(0.564)/(58.5)` = 0.0096mol

Number of moles of LiCl =
`(0.857)/(42.5)` = 0.02mol

Sum of moles = 0.02mol + 0.0096mol + 0.02mol = 0.0496mol

Mole fraction of KCl =
`(0.02)/(0.0496)` = 0.4