$$$ Quiz $$$ Solutions

$$$ Quiz $$$

Solutions

Liquids that are soluble in each other

miscible

Liquids that are not soluble in each other

immiscible

When a solution contains more solute than it should.

supersaturated

When you can’t add more solute to the solution without it precipitating out.

saturated

Solubility is usually expressed as ….

grams of solute per 100 g of solvent

What is the formula for Henry’s Law? What do the variables stand for?

2

2

1

1

P

S

P

S S = Solubility

P = Pressure

Roughly speaking, what is the difference between a dilute and concentrated solution?

A dilute solution has a low amount of solute and a concentrated solution has a high amount of solute

What is the molarity of a solution that has 15 moles of

a solute in 3 liters of solution?

5 M

What are the units of molarity?

Mole/Liters

How many moles of solute are in 1500 mL of a 0.333 M solution?

0.5 moles

What is the name for a solid that is dissolved in a solution?

Solute

What is the name for a liquid that does the dissolving in a

solution?

Solvent

What mass of CsBr (cesium bromide) is needed to make

1.5 L of a 3.0M solution?

212.8 g/mol x 4.5 moles = 957.6 grams CsBr

True or False. When you dilute a solution, the moles of the solution

stay the same.

True

If 5.0 mL of 5.0M HBr is used to make a 500 mL aqueous

solution, what is the molarity of the dilute solution?

M1V1=M2V2, (5)(5)=500x = 0.05M

A solute plus a solvent gives a _______.

Solution

What is the formula for mass percent?

mass solute (g) x 100%mass solution (g)

What is the formula for parts per million (ppm)?

mass solute (g) x 106

mass solution (g)

What is the formula for volume percent?

volume solute (mL) x 100%volume solution (mL)

If the percent mass of a solution weighing 300 g is 6%, what is the

mass of the solute?

.06 = x/300gx = 18 g

Name the three colligative properties we studied?

- Vapor pressure lowering- Boiling point elevation- Freezing point depression

What is the formula for freezing point depression?

Tf = Kf x m x i

What is the formula for freezing point depression?

Tf = Kf x m x i

What type of compounds are always electrolytes?

Ionic compounds

What is the formula for molality?

moles solute/kg of solvent

What is the Van’s Hoff factor of MgO?

2

What is the Van’s Hoff factor of Na2O?

3

What is the Van’s Hoff factor of SF3?

1, molecular (covalent) compound

If you calculate a Tf of -12.3 oC for a pure substance that melts at 3.4oC, what is its new melting

point?

-8.9oC