Determine the osmotic pressure (in atm) , at 80.2 o F, of an aqueous Iron (II) nitrate solution whose mole fraction of solute is 0.002696.
Density solution = 1.11 g/mL

- Lena772

- Stacey Warren - Expert brainly.com

Hey! We 've verified this expert answer for you, click below to unlock the details :)

- katieb

I got my questions answered at brainly.com in under 10 minutes. Go to brainly.com now for free help!

- Lena772

PV= nRT
So Posm = nRT/V
R= 0.08206 L*atm/mol*k
T= 80.2F = 299.928 K
V = calculate somehow using density
n = reverse mole fraction calculation to find total moles of solution

- Lena772

@taramgrant0543664 @photon336 Can you guys assist me in reversing the mole fraction equation to find total moles of solution and then using that calculation with the density to find volume?

- taramgrant0543664

V=m/d
where v is volume, m is mass and d is density

Looking for something else?

Not the answer you are looking for? Search for more explanations.

## More answers

- Lena772

right, but i can't find the mass of the solution until i reverse the mole fraction and find moles of total solution

- Lena772

I think? Mole fraction = (moles solute) / (moles solute + moles solv ). We are given moles of solute, but I don't know where to go from here. :(

- taramgrant0543664

Yes that is the formula

- taramgrant0543664

You're not given moles of solvent?

- Lena772

@Abhisar @pooja195 @zepdrix @abb0t

- Lena772

Nope. :/

- taramgrant0543664

Hmmm... I don't know to tell you sorry I've only touched on osmotic pressure stuff none of my profs or teachers really talked much about it so I don't want to lead you on the wrong direction

- Lena772

Do you know anyone online that can help me? @taramgrant0543664

- taramgrant0543664

I think you got a majority of the ones that could hopefully help

- Lena772

@abb0t Do you think you can help me?

- Lena772

@NoelGreco Hi! Can you please help me?

- mayankdevnani

@Lena772 can you find out molality ?

- Lena772

yes moles solute/kg solvent. But I don't know the moles of solute.

- mayankdevnani

Here is a formula :-
\[\large \bf Molality=\frac{X_{solute}\times 1000 }{(1-X_{solute}) \times M_{solvent}}\]

- mayankdevnani

and then use this :-
\[\large \bf Molarity=\frac{molality \times density \times 1000}{molality \times Molar~ mass~ of~ solute+1000}\]

- mayankdevnani

hope you can find molarity

- Lena772

Molal = (0.002696 mol Solute * 1000) / ( 0.997304 * molality of solvent) , BUT idk the molality of the solvent

- mayankdevnani

its molar mass of solvent

- mayankdevnani

not molality of the solvent
Remember molality is denoted by small m i.e `m`

- Lena772

Molal = (0.002696 mol Solute * 1000) / ( 0.997304 * 175.8948)

- mayankdevnani

after you find out molarity !
Use this :-
\[\large \bf Osmotic~Pressure(\pi)=Molarity \times RT \times vant~hoff~factor\]

- Lena772

0.015368778 molal ?

- mayankdevnani

i don't know.
Use calculator

- mayankdevnani

i am here to give you HINTS as possible

- Lena772

molality = 0.94396197
0.94396197 * 0.08206 * 299.928 K * van hoult?

- mayankdevnani

you don't know vant hoff factor ?

- mayankdevnani

denoted by `i`

- mayankdevnani

@Lena772 then first learn this term and then solve the rest of question

- mayankdevnani

any problem ???

- Lena772

Would the factor be 4 because there is 3 pieces of iron nitrate and 1 piece of water molecule?

- Lena772

@mayankdevnani

- mayankdevnani

nope !
try again

- Lena772

What's wrong about it?

- mayankdevnani

see the oxidation state of iron in question.
You took the oxidation state as +3

- Lena772

So van hoff is 3 ?

- mayankdevnani

yup

- Lena772

I get 69.7 atm. That's sounds extreme. Can you just plug those in and see if you get the same value?

- mayankdevnani

lol
but i don't have much time to solve !
Sorry !
Better luck ,Next time

- mayankdevnani

i have to go now !
Bye ! @Lena772
Its been a nice time with you ! :)

- mayankdevnani

MEDAL for your HARDWORK and keen interest on solving this question !

- mayankdevnani

REMEMBER :- Don't suppose that i am a professor, i am (18)-

Looking for something else?

Not the answer you are looking for? Search for more explanations.