How do you calculate the χacetone and χcyclohexane in the vapor above the solution. P°acetone = 229.5 torr and P°cyclohexane = 97.6 torr?

A solution is prepared by mixing 4.40 mol of acetone with 1.45 mol of cyclohexane at 30°C.

A solution is prepared by mixing 4.40 mol of acetone with 1.45 mol of cyclohexane at 30°C.

1 Answer
Write your answer here...
Start with a one sentence answer
Then teach the underlying concepts
Don't copy without citing sources
preview
?

Answer

Write a one sentence answer...

Answer:

Explanation

Explain in detail...

Explanation:

I want someone to double check my answer

Describe your changes (optional) 200

2
Mar 21, 2018

Answer:

Well by definition....the vapour pressure of EACH component is PROPORTIONAL to #chi_("component"(g))#...

#P_"component" = chi_("component"(g))P_"solution"#

Explanation:

Well in solution, the #"mole fraction"# is

#chi_("component"(l))="moles of component"/"Total moles in solution"#

So,

#chi_("acetone"(l))="moles of acetone"/"moles of acetone + moles of cyclohexane"#...

#=(4.40*mol)/(4.40*mol+1.45*mol)=0.752.#

And clearly....#chi_("cyclohexane"(l))=1-chi_("acetone"(l))=1-0.752=0.248#.

And so

#P_"acetone"=chi_("acetone"(l))xx229.5*mm*Hg=0.752xx229.5*mm*Hg=172.6*mm*Hg#

#P_"cyclohexane"=chi_("cyclohexane"(l))xx97.6*mm*Hg=0.248xx97.6*mm*Hg=24.2*mm*Hg#

#P_"solution"=P_"acetone"+P_"cyclohexane"={172.6+24.2}*mm*Hg#

#-=196.8*mm*Hg#

But in the vapour phase, the vapour pressure of EACH component is PROPORTIONAL to #chi_("component"(g))#...

#P_"component" = chi_("component"(g))P_"solution"#

As always, the vapour pressure is ENRICHED with respect to the more volatile component....here acetone...

Was this helpful? Let the contributor know!
1500
Impact of this question
15 views around the world
You can reuse this answer
Creative Commons License