have some problems with thoery in chem class. i have a test tomarrow.

can someone answer these questions for me? i have a few problems with understanding them.


when a nonvolitile solute is dissolved in a solvent, it causes

A) Freezing point lowering
B)Boiling point elevation
C) Vapor Pressure Lowering
D) ALL of the above.

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What is the vapor pressure at 20.0 Celsius of a colution of 8.00g of C(10)H(8) solute in 30.0g of C(6)H(6) solvent if the pure solvent has a vapor pressure of 75.0 mmHG?

(Molar mass of C(10)H(8)= 128.18 and Molar Mass of C(6)H(6)= 78.12

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The normal freezing point of a certain solvent is 53.1 Celsius; its k(f) value is 7.10(Celsius/m). if a solution has 1.52 g of an ammonia solute in 10.0 g of the solvent what will be the freezing point of the solution? (Molar Mass of NH(3)= 17.04
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water has a normal boiling point of 100.0 degrees celsius and a k(b) value of .52 (Celsius/m). if 35.0 g of a solute dissolved in 300.0 g of water causes the water to boil at 100.177 degrees celsius, what is the molar mass of the solute?
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dont answer them for me, just please give me some help please. im havin some serious trouble here.