One beaker has 4x10^-6 moles MgCl2 in 40 mL solution, with a Ksp of 4.1x10^-20

[hospitaldoctor1]

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You have two beakers of solutions. One beaker has 4x10^-6 moles MgCl2 in 40 mL solution, with a Ksp of 4.1x10^-20. The other has 4x10^-6 moles NaCl, in 50mL, Ksp of 3.6x10^-11.
What is the osmotic pressure, boiling point temperature, and vapor pressure for each? Which beaker is each property higher for?


How do you calculate this exactly please? (showing work)
Don't you need to calculate IP first, then compare it to Ksp... then find the molarity accordingly? How do you do that exactly?
Thanks

 

[Seraph 84]

Look for equations in your test prep that involve osmotic pressure and solubility.

 

[boaz]

Those ksps sound gawdawfully LOW.

 

[minutemen11]

You have two beakers of solutions. One beaker has 4x10^-6 moles MgCl2 in 40 mL solution, with a Ksp of 4.1x10^-20. The other has 4x10^-6 moles NaCl, in 50mL, Ksp of 3.6x10^-11.
What is the osmotic pressure, boiling point temperature, and vapor pressure for each? Which beaker is each property higher for?


How do you calculate this exactly please? (showing work)
Don't you need to calculate IP first, then compare it to Ksp... then find the molarity accordingly? How do you do that exactly?
Thanks

are you serious? you asked this very same question already and it has been answered really well exhaustively!
http://forums.studentdoctor.net/showthread.php?t=649298

if you are not studying for the MCAT then you should probably ask this in a chemistry forum because the mcat will never ask you do to this. At the most extreme case it will ask for qualitative measurements; if the IP is greater than Ksp then you get precipitate, if IP is less than Ksp you can add more reactant.

after you reread TheBoondocks first answer to your question you see that the NaCl has more ions dissolved than MgCl2. Now, if you have more ions you will have more intermolecular forces. This means you effectively RAISE the boiling point, a substance with a HIGHER boiling point will have a LOWER vapor pressure.

Osmotic pressure is the pressure of the SOLUTE, thus, since NaCl has MORE ions there will be a HIGHER osmotic pressure than MgCl2.

If you want actual values consult your textbook, actual values for this will never be tested!

 

[hospitaldoctor1]

How do you do this qualitatively?

 

[Zona Pellucida]