[nicolodn]

Colligative properties of solutions?
1. 0.1M NaCl
2. pure water
3. 0.1 M CaCl2
4. 0.1 M acetic acid
5. 0.1M glucose

Could someone answer and explain why;
- list them from lowest to highest BoilingPt
- lowest to highest MeltingPt
- highest osmotic pressure
- lowest to highest vapour pressure.

Also, is melting pt=freezing pt?

[Fluorine]

Highest osmotic pressure is straight forward. First you should know what osmotic pressure is and how it's calculated.

The formula is Π = iMRT

where;
Π = osmotic pressure
i = number of dissociated particles
M = molarity
R = gas constant
T = temperature

R is a constant, M is the same, and we have to assume T is the same for all. The main factor of consideration for this question is i. Which one of these would dissociate into the most particles? If more than one has the same i consider which would dissociate partially which would dissociate fully.

[Nicolas88]

I will not give you the answers to this question but i will show you how 
Boiling point:
All the solutes above are dissolved in water , and as we know the Bp of water is 100 C
to calculate the difference in boiling point after dissolving a substance :
T_b= X*T^*_b
where
X= mole fraction
T_b= difference in boiling point
T^*_b = boiling point of pure substance

you can use the same equation for the vapor pressure, freezing point , melting point..

after you solve all these you will know if the melting pt=freezing pt.