Question

Calculate the mole fraction of each component in a solution with 6.87 g of sodium chloride (NaCl) dissolved in 65.2 g of water. Work must be shown in order to earn credit.

Answer 1

mole fraction of NaCl = 0.03145.

mole fraction of water = 0.9686.

Step-by-step explanation:

• Mole fraction is an expression of the concentration of a solution or mixture.

• It is equal to the moles of one component divided by the total moles in the solution or mixture.

• The summation of mole fraction of all mixture components = 1.

mole fraction of NaCl = (no. of moles of NaCl) / (total no. of moles).

no. of moles of NaCl = mass/molar mass = (6.87 g)/(58.44 g/mol) = 0.1176 mol.

no. of moles of water = mass/molar mass = (65.2 g)/(18.0 g/mol) = 3.622 mol.

∴ mole fraction of NaCl = (no. of moles of NaCl) / (total no. of moles) = (0.1176 mol)/(0.1176 mol + 3.622 mol) = 0.03145.

∵ mole fraction of NaCl + mole fraction of water = 1.0.

∴ mole fraction of water = 1.0 - mole fraction of NaCl = 1.0 - 0.03145 = 0.9686.