Chemistry

Question 1

Acetate

Answer 1

CH3CO2-

Question 2

Bicarbonate

Answer 2

HCO3-

Question 3

Cyanide

Answer 3

CN-

Question 4

Nitrate

Answer 4

NO3-

Question 5

Nitrite

Answer 5

NO2-

Question 6

Perchlorate

Answer 6

ClO4-

Question 7

Carbonate

Answer 7

CO3 2-

Question 8

Sulfate

Answer 8

SO4 2-

Question 9

Sulfite

Answer 9

SO3 2-

Question 10

Ammonium

Answer 10

NH4+

Question 11

Oxidation State Rules

Answer 11

1. Standard state is 0
2. Sum in neutral is 0
3. Group 1 = +1, Group 2 = +2
4. Flourine is -1, as do all halogens
5. Hydrogen has a +1 when bonded to something more electronegative otherwise -1
6. Oxygen is -2

Question 12

Order of electronegativities

Answer 12

FONClBrISCH (fawn-cull-brish)

Question 13

Outermost shell of electrons

Answer 13

d = -1 from period number, ex: Period 4 but 3d
f = -2 from period number ex: Period 7 but 5f

Question 14

Exceptions to filling rules

Answer 14

Chromium (Cr) and family (down)
Copper (Cu) and family (down),

Remember: 4s removed before 3d

Question 15

Formal Charge

Answer 15

FC = V - 1/2B - L

Question 16

Which molecules can participate in hydrogen bonding?

Answer 16

H must be covalently bonded to F, O, or N

Question 17

When a bond is formed is energy released?

Answer 17

YES, deltaH < 0. Why we must PUT IN energy to break a bond.

Question 18

Heat of reaction

Answer 18

Hproducts - Hreactants

If products have stronger bonds than reactants, exothermic and energy released from the system (negative heat of reaction H)

If products have weaker bonds, endothermic and energy absorbed overall (positive heat of reaction H)

Another method is to use bond dissociation energy:
deltaHrxn = sigma (BDE bonds broken) - sigma(BDE bonds formed)

Question 19

STP vs Standards Conditions

Answer 19

STP: 0C

Standard Conditions: 25C or 298K

Question 20

Heat of formation (Hf)

Answer 20

Energy change associated with making one mole of a compound from its constituent elements in standard state

Positive - input of heat required
Negative - gives off energy

Question 21

Entropy Quick Tips

Answer 21

gases > liquids > solids
- particles in solution more than undissolved
- two moles more than 1 mole
Sreverse = - S forward

Question 22

Boyle’s Law

Answer 22

P, V Inverse

Question 23

Charles Law

Answer 23

V, T Direct

Question 24

Gay-Lussac’s Law

Answer 24

P, T Direct

Question 25

Graham's Law of Effusion

Answer 25

rms Va / rms Vb = sqrt(mb/ma)

Question 26

Equilibrium Constant vs. Rate Constant

Answer 26

Rate Constant MUST use experimental data: rate = k[A]^x{B]^y, order = x + y Equilibrium constant, Keq, use coefficients in equation - constant at a given temperature

Question 27

Changing temperature of rxn mixture

Answer 27

If adding heat and exothermic: consider heat like a product endothermic: consider heat like a reactant ** lowering temperature favors the exothermic rxn, while raising the temperature favors the endothermic one

Question 28

Phase Solubility Rules

Answer 28

1. Solubility of solids in liquids tends to increase with increasing temp 2. Solubility of gases in liquids tends to decrease with increasing temperature 3. Solubility of gases in liquids tends to increase with increasing pressure

Question 29

Salt Solubility Rules

Answer 29

1. All Group I and ammonium (NH4+) salts are SOLUBLE 2. All nitrate (NO3-), perchlorate (ClO4-), and acetate (C2H3O-) salts are SOLUBLE 3. All silver, lead, and mercury salts are INSOLUBLE, except for their nitrates, perchlorates, and acetates

Question 30

Solubility Product Constant

Answer 30

Ksp measures extent to which a salt will dissolve; at equilibrium the solution is saturated

Question 31

Do Complex Ions formation increase/decrease solubility?

Answer 31

Increase solubility; often metals binding with ligands like NH3

Question 32

Acid Ionization Constant, Ka

Answer 32

Ka essentially Keq Ka < 1 = weak acid and reactant favored

Question 33

List of strong acids

Answer 33

HI, HBr, HCl, HClO4, H2SO4, HNO3

Question 34

List of strong bases

Answer 34

Group 1 Hydroxides, NaOH Group 1 Oxides, Li2O Some Group 2 Hydroxides, Ba(OH)2, Sr(OH)2, Ca(OH)2 Metal Amids, NaNH2 weak base: ammonia and amines

Question 35

Autoionization of Water

Answer 35

Kw = [H3O+][OH-] = 1 * 10^-14 at 25C Increases with increasing temperature

Question 36

pKa value means

Answer 36

If low --> strong acid pka = - logKa So large Ka leads to a low pKa pKa + pKb = 14

Question 37

Ka * Kb

Answer 37

= Kw = 1 * 10^-14

Question 38

Henderson Hasselback Equation

Answer 38

pH = pKa + log(conj base/weak acid) ideal buffer: pH = pKa

Question 39

OIL RIG

Answer 39

Oxidation is electron Loss | Reduction is electron Gain

Question 40

Galvanic Cells: Anode vs Cathode

Answer 40

Anode - oxidation occurs here, Zn --> Zn2+ + 2e- Cathode - reduction occurs here, Cu2+ + 2e- --> Cu electrons flow from excess at anode to cathode

Question 41

Higher 1st ionization energy means more/less reactive?

Answer 41

Less reactive, since need to put in more energy to remove the first valence electron

Question 42

Disproportionation reaction

Answer 42

Oxidation and reduction to same element

Question 43

How to remember oxidation and reduction in electrochemistry?

Answer 43

AN OX, RED CAT

Question 44

A battery discharging behaves like an...

Answer 44

Galvanic (voltaic cell) and a charging battery is like an electrolytic cell

Question 45

The number of moles of metal plated can be found for a given current over a given amount of time using the equation

Answer 45

mol metal = I * t / n * F