Solutions

Question 1

What is the difference between saturated and unsaturated solution?

Answer 1

In a saturated solution, the maxiumum amount of solute is dissolved in the solvent. In unsaturated solutions, there is less than the maximum amount of solute dissovled in the solvent.

Question 2

What are the soluble salts?

Answer 2

Group 1 Metal cations
NO3(-)
ClO4(-)
C2H3O2(-)
NH4(+)

Soluble trumps insoluble

Question 3

What are the insoluble salts?

Answer 3

Ag(+)
Pb2(+), Hg2(+)
OH(-)
S(2-)
CO3(2-), PO4(3-)

Insoluble is trumped by soluble

Question 4

What are electrolytes?

Answer 4

Substances that have a natural (+) or (-) electrical charge when dissolved in water.

Helps regulate chemical reactions in body, maintains balance between fluids in and outside of the cells

Question 5

What is the difference between a strong, weak and non- electrolytes

Answer 5

Strong - fully dissociates in water
Weak - incompletely dissociates in water
Non - does not dissociate in water

Question 6

What are the groups of strong electrolytes?

Answer 6

Soluble Ionic Compounds
Strong Acids (HCl, HBr, HI, HClO4, H2SO4, HNO3)
Strong Bases (Group I Metal Hydroxides, Ba(OH)2, Sr(OH)2, Ca(OH)2)

Question 7

What are the groups of WEAK electrolytes?

Answer 7

Weak acids: (HF, HCN, CH3COOH)
Weak bases: (NH3, CH3NH2)

Question 8

What are non-electrolytes?

Answer 8

Molecular compounds that aren’t acidic/basic. (eg, glucose, methanol)

Question 9

Solids are more soluble at?

Answer 9

High temperatures

Question 10

Gases more soluble at?

Answer 10

Low temperatures
High pressure

Question 11

What is Beer’s Law

Answer 11

Light absorption is directly proportional to path length and concentration of solution
Formula: A=⍷lc

A = absorbance, ⍷ = molar absorptibity coefficient (M-1cm-1) l = path le

Question 12

What is molarity?

Answer 12

Number of moles of solute/1 L solution; M

Question 13

What is molality?

Answer 13

Number of moles of solute/1 Kg of solvent; m

Question 14

What is normality?

Answer 14

It expresses concentration in terms of equivalents of one chemical species that react stoichiometrically with another chemical species
N = n x M

N = normality, n = number of equivalents, M = molarity

Question 15

Mole fraction?

Answer 15

Xa = moles A/total moles
Xb = moles B/total moles

Question 16

What are colligative properties?

Answer 16

Properties that depend upon concentration of solute molecultes or ions, but not upon the identity of the solute.
Ex. Freezing-point depression, boiling point elevation (adding salt to water), vapor-pressure depression, osmotic pressure

Question 17

What are non-colligative properties?

Answer 17

Properties that depend on the identity of the dissolved species and the solvent
Ex. surface tension, viscosity, color, solubility, and density.

Question 18

What is boiling point and how does it change as altitude increases?

Answer 18

When the vapor pressure = atmospheric pressure.
As elevation increases, atmospheric pressure decrease: lower atmospheric pressure = lower vapor pressure, meaning lower boiling point.
As elevation decreases, atmostpheric pressure increases: higher atmostpheric pressure = hight vapor pressure, and hight BP.

Question 19

Raoult’s Law

Vapor Pressure Depression

Answer 19

Pa = Xa x P*a

Pa - vapor pressure of solution, Xa = mole fraction of solvent, P*a = pure vapor pressure of solvent

Question 20

Boiling-poing Elevation Formula

Answer 20

⍙Tb = kb * i * m

⍙Tb = amont boiling point increases
kb = solvent’s boiling-point elevation constant
i = solute’s van’t Hoff factor (number of particles solute breaks into when dissolved).
m = molal concentration of solution

Question 21

Freezing-Point Depression Formula

Answer 21

⍙Tf = -kf * i * m

⍙Tf = amont freezing point decreases
kf = solvent’s freezing-point elevation constant
i = solute’s van’t Hoff factor (number of particles solute breaks into when dissolved).
m = molal concentration of solution

Question 22

Osmotic Pressure

Answer 22

Pressure it would take to stop osmosis from happening.
Formula: ⎍ = i * M * R * T

⎍ = ostomic pressure (atm)
i = van’t hoff factor
M = molarity of solution
R = universal gas constant (0.0821 Latm/Kmol)
T = temp in Kelvin

Question 23

Polar bonds are formed when two or more atoms are bonded together with different (blank)?

Answer 23

Electronegativity