Question

of Hccalculator the mole fractionl and H2o in a solution of hydroloric acid in water Containing 30% Hcl by weight​

Answer 1

Answer:

0.1 and 0.9, respectively.

Explanation:

You know that your solution is 20% hydrochloric acid by mass, which means that every 100 g of this solution contain 20 g of hydrochloric acid, the solute.

To make the calculations easier, pick a sample of this solution that has a mass of exactly 100 g. Since you already know that this sample contains 20 g of hydrochloric acid, you can say that the mass of water, the solvent, will be

   mass of solventmass H2O=mass of solution100 g−mass of solute20 g

   mass H2O=80 g

Nest, use the molar mass of hydrochloric acid and the molar mass of water to convert the masses to moles.

  20g

⋅1 mole HCl36.46g

=0.5485 moles HCl

80g

⋅1 mole H2O18.015g

   =4.4407 moles H2O

Now, the mole fraction of hydrochloric acid is given by the ratio that exists between the number of moles of hydrochloric acid and the total number of moles present in the solution.

   χHCl=moles HCltotal moles

In this case, the mole fraction of hydrochloric acid will be

   χHCl=0.5485moles

(0.5485+4.4407)moles

   =0.1−−−

To find the mole fraction of water, use the fact that the mole fractions of the solute and of the solute, respectively, must add up to give 1.

   χH2O=1−χHCl

You will find

   χH2O=1−0.1=0.9−−−

The answers are rounded to one significant figure