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Flashcards in Review 6 Deck (39):
1

Relate standard ∆G˙ with ∆Grxn

∆G˙ = ∆Grxn + RTlnQ

2

Negative enthalpy is exothermic or endothermic?

Exothermic

3

Positive enthalpy is exothermic or endothermic?

Endothermic

4

What phase has the highest entropy?

What has the lowest?

Gas = highest entropy, solid = lowest

5

Under what conditions are gases real and not ideal?

Low pressure
High temperature

6

Ideal gases

No attractive forces b/w them

7

Graham's Law of effusion

Higher molar mass => leaks more slowly through hole

8

How do you calculate pressure of gas?

Subtract vapor pressure of water from its measured pressure

9

Average kinetic energy is directly proportional to _____

Temperature of gas in kelvin

10

Another equation for n (moles)

n = m/M

- m = mass of gas
- M = molar mass

11

How many cm^3 in a liter?

1000

12

Coordinate covalent bond

Bond where one molecules acts as Lewis acid (accepts electrons) and the other acts as Lewis base (donates e-)

- Play role in complex ions

13

Common ion effect on solubility

Decreases solubility

14

Raoult's Law (effect of solutes on boiling point and vapor pressure)

Solutes => decrease vapor pressure => increase boiling point

15

Effect of solutes on freezing point

Depresses freezing point by disrupting crystal lattice => more energy must be taken out

16

Solubility of gases in liquids is directly proportional to ______

Atmospheric pressure

17

What molecules would have positive deviation from Raoult's Law?

Negative deviation?

Unlike molecules => want to get out of solution => higher vapor pressure than expected = positive deviation

Like molecules = negative deviation

18

Formation of complex ions => what?

More molecules of solid will dissociate (ions are being removed from solution due to complexing)

19

Solution

Mixture of uniform appearance (homogenous)

- Can be solid-solid, gas-solid, gas-gas, etc.

20

Molality

Moles of solute/kg of solvent

21

Boiling point/freezing point change

∆T = i*K*m

- i = # of ions it dissociates into
- K = initial boiling/freezing point
- m = molality

22

How many liters of 2 M Ba(OH)2 are needed to titrate a 4 L solution of 6 M H3PO4?

18 L

- NaVa = NbVb
- N (normality) = molarity * number of OH or H+
- Na of Ba(OH2) = 2*2 = 4
- Nb of H3PO4 = 3*6 = 18

23

3.4 x 10^-6 Ka correlates to what pH?

5.66

- 6 - 0.34 = 5.66 pH

24

Gram equivalent weight of phosphoric acid

33g

- H3PO4
- Molar mass = 98g
- 3 protons => divide molar mass by 3 for weight of one acid/base

25

log(1/10)

-1

26

Acids ending in -ic are derivatives of anions ending in _____

-ate => -ic

- Attic

27

Acids ending in -ous are derivatives of anions ending in _____

-ite => -ous

- Iteous

28

What has more O: -ate or -ite?

-ate

29

Chlorate chemical formula

Chlorite chemical formula

ClO3-

ClO2-

30

Oxidation = ____ (more/less) bonds to O or ____ bonds to H

More bonds to O
Less bonds to H

31

Disproportionation reaction

Element appears with different oxidation states in two different products

32

Concentration cell

Type of galvanic cell where both electrodes are made of same material

33

E˙cell = ____ - _____

E°cell = E°red,cathode − E°red,anode

34

Electrolytic cell process

Break compound into constituent ions

- Cations => cathode
- Anions => anode

35

Relate ∆G and E

∆G = -nFE

- n = moles of electrons (from half reactions)
- F = Faraday's constant

36

In a galvanic cell, species with higher reduction potential is _____

Reduced

37

Relate ∆G and Keq

∆G = -RTln(Keq)

38

If Keq

Negative lnKeq => positive ∆G

39

Lead-acid batteries have ____ energy density

Ni-CD batteries have ____ energy density

NiMH batteries have _____ energy density

Low energy density

Ni-Cd = higher energy density

NiMH = highest energy density