Hello all!(: I need help with a problem involving vapor pressure, boiling point and freezing point, in relation to solutions.

So the question is: An equal number of moles of KI (potassium iodide) and MgI2 (magnesium iodide) are dissolved in equal volumes of water.

Which solution has the higher boiling point?
Which solution has the higher vapor pressure?
Which solution has the higher freezing point?

If someone could also explain WHY, that would be lovely(: Thank you all in advance!

Question

Hello all!(: I need help with a problem involving vapor pressure, boiling point and freezing point, in relation to solutions. 

So the question is: An equal number of moles of KI (potassium iodide) and MgI2 (magnesium iodide) are dissolved in equal volumes of water. 

Which solution has the higher boiling point?
Which solution has the higher vapor pressure?
Which solution has the higher freezing point? 

If someone could also explain WHY, that would be lovely(: Thank you all in advance!

sweetburger · Answer

Ok sorry i know im responding to this late I will attempt to answer your question
First off MgI2 dissociates into more ions then KI does so MgI2 has a greater affect on the colligative properties which causes the solution to have a higher boiling point and a lower freezing point. Now because the KI dissociates into only 2 ions it has a lesser affect on the solution meaning it is the solution with a higher freezing point and a higher vapor pressure