Solutions

Question 1

Molarity:

Formula:

Answer 1

Describes the number of moles of a solute in 1 liter of solution.

• M= mol solute/1iter solution*
• mol of solute=weight of solute/fomrula weight*

Question 2

A substance that has the ability to absorb moisture from the atmosphere is called:

Answer 2

Hygroscopic

Question 3

Solution:

Answer 3

A homogenous mixture of two or more substances that end up looking like only one of the substances.

Question 3

Molality:

Answer 3

More practical to use when dealing with colligative properties. Describes the number of moles of solute per kilogram of solvent.

m=mol of solute/kg solvent

Question 4

5 kinds of solutions:

Answer 4

1. Saturated
2. Unsaturated
3. Supersaturated
4. Concentrated
5. Dilute

Question 4

Molal Boiling point:

Answer 4

1 mol of an nonvolitile, nonelectrolyte, added to 1kg of water raises the boiling point of the water by .51^oC.

Change in T_b= K_bx m

m= change in T_b/K_b

Question 6

Oxides of alkali metalls and alkaline earth metals react with water to form…

Explain:

Answer 6

metal hydroxide solutions.

The oxygen ion gets picked off by the water molecule, leaving the metal atom as a cation and making the neutral water molecule into a negative hydroxide anion.

Question 6

Molal freezing point constant:

Answer 6

Each mole of a nonvolitile, nonelectrolyte, in 1 kg of water, will lower the freezing point by 1.86^oC

molal freezing point constant for water= -1.86^oC.

change in T_f= K_f x m

or

m= change in T_f/k_f

Question 8

Acid anhydrides:

Basic anhydrides:

Answer 8

Nonmetal oxides, which form acid when added to water.

Metal oxides, which form bases when added to water.

Question 9

Electrolyte:

Answer 9

A soluble ionic solid in aqueous solution. It conducts electricity.

Question 11

Hydrates:

Answer 11

Compounds that contain water within their crystal lattice structure. The water they contain is called water of hydration.

To find the percentage weight of the water of hydration, dvide the weight of the water molecules by the entire formula weight.

Question 12

Solute:

Answer 12

The substance of less quantity, that is getting dissolved into the solvent.

Question 14

Many nonmetal oxides react with water to form…

Explain:

Examples of these oxides:

Answer 14

acids.

The nonmetal oxide will pick off the oxygen atom from the water molecule, making itself an acid, and leaving the hydrogen atoms as a molecule.

H₂O+ N₂O5, CO₂, SO₂, SO3, and PO_3.

Question 14

Placing a solute in a solvent _____ the vapor pressure.

Mole fraction:

Answer 14

lowers

This is because the vapor pressure of the solution is due to both the solute and solvent.

Mole fraction:

Total mol in a solution= mol of solute + mol of solvent.

all mole fractions must add up to 1

Question 15

Raoult’s law:

Answer 15

Vapor pressure is contributed by one of the liquids is equal to the mole fraction of that substance multiplied by the vapor pressure of that substance in it’s pure form.

P_A=X_A P^o_A

Applies to ideal vapor pressure, and to solutions in which the solute is a solid with no vapor pressure.

Question 16

In solutions, density=?

Answer 16

weight/volume

Question 17

Colligative properties:

Answer 17

properties that vary according to the ratio of the weights of the solute and solvent.

ex boiling point, freezing point, and vapor pressure.

Question 18

Solvent:

Answer 18

The substance of greater quantity, that is doing the dissolving.

Question 19

When an anhydrous salt abosorbs enough water to dissolve themselves in their own water of hydration, they are called:

Answer 19

Deliquescent

Question 20

Nonelectrolytes