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1

solution

composed of a solute and solvent, each of which can be a solid, liquid or gas

2

Molarity (M)

amount of solute(moles) / volume of solution (L)

3

Mass Percent

(mass of solute / mass of solution) x 100

4

Volume Percent

(volume of solute / volume of solution) x 100

5

Mass Volume Percent

(mass of solute (g) / volume of solution (mL)) x 100

6

Parts Per Blank

ppm (parts per million) = mg solute / L solution

or: (g solute / g solution) x 1,000,000

ppb (x10^9)
ppt (x10^12)

7

Mole Fraction (Xi) and Percent

Xi = moles of i / total solution moles

mole percent = 100(Xi)

8

Molality (m)

independent of temperature unlike molarity

amount of solute (moles) / mass of solvent (kg)

9

Normality (N)

(# of equivalents)(Molarity)

10

Solubility

amount of solute that can be dissolved in a solvent

= grams of solute dissolved / given mass or volume of solvent

increases with temperature (with few exceptions)

11

miscible

ability of 2 compounds to homogeneously mix in a solution

-like dissolves like (ex: polar: water, ionic, salts, alcohols, water-soluble compounds; or nonpolar: hydrocarbons, molecular compounds, oils, gasoline, grease, fat, fat-tissue, many organics)

12

enthalpy of solution (delta H soln)

energy involved in mixing a solute and solvent to form a solution

delta H soln > 0 (+) endothermic and feels cold
delta H soln < 0 (-) exothermic and feels hot

13

ideal solution

when delta H soln = 0 (occurs for hydrocarbon (organic) mixtures)

14

Saturated

The saturated line represents the point where dissolution and crystallization are both occurring and in equilibrium with each other

15

Undersaturated

region of the graph occurs when the solvent can dissolve more solute than is available (located on bottom part - kind of where gases would be)

16

Supersaturated

occurs when solution has more solute in solutions than equilibrium allows.

17

Fat-soluble

compounds that are essentially nonpolar; recognized for being composed of mostly C and H atoms and possibly one OH group. (Ex: Vitamin A)

18

Water-soluble

compounds that are polar; recognized for having numerous OH groups (polar) along with C and H atoms (ex: Vitamin C)

19

Temperature Effects: Solids dissolved in liquids

solubility increases as temperature increases

20

Temperature Effects: Gasses dissolved in liquids

solubility of gas in liquid decreases as temperature increases

21

Pressure Effects: (Gases dissolved in Liquids)

As pressure increases, the solubility of gas in liquid increases.

22

Henry's Law

Describes pressure effects of pressure increasing - solubility of gas in liquid increases.

C = kPgas
- C: solubility or concentration
- k: henry's law constant (sometimes 1/k)
- Pgas: pressure of the gas

Sometimes written as:
k = C1/P1 = C2/P2

23

Raoult's Law

Describes why adding a solute to a solvent causes the solvent to have a lower vapor pressure (or partial pressure, Pa). The partial pressure (Pa) is equal to the mole fraction (Xa) multiplied by the pure pressure of the solvent.

Combine Dalton's law if question asks about vapor pressure. Dalton's: Ptot = XaPa^o + XbPb^o

24

Negative deviation

Mixture of polar molecules

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Positive deviation

Mixture of nonpolar and polar molecules

26

Fractional distillation

When separating mixtures, fractional distillation is used in stages to distill, separate out the liquid, condense the vapor, and re-distill.