Chapter 12- Electrochemistry Flashcards

1
Q

Location of oxidation and reduction

A

AN OX (anode- oxidation) and RED CAT (cathode- reduction)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is an electrochemical cell and name 3 types

A

Contained system where oxidation-reduction reactions occur. Ex: galvanic (aka voltaic)- spontaneous, electrolytic- nonspontaneous, and concentration-spontaneous

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Electromotive force (EMF)

A

Voltage or electrical potential difference of the cell. If + then spontaneous release of energy. If - then nonspontaneous absorption of energy.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Movement in electrochemical cells

A

Movement of electrons- from anode to cathode. Current- from cathode to anode.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Relationship between free energy and electromotive force

A

Always have opposite signs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Electrolytic cells

A

Nonspontaneous and require energy input (🔺G = +) and thus type of redox reaction driven by an external violate source is called electrolysis (chemical compounds are decomposed)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Faradays constant (one faraday)

A

1 F = 96,485 C (on MCAT round number to 10^5 C/mol e-)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Electrodeposition equation. Helps determine number of miles of element being deposited on a plate.

A

mol M = It / nF (Moles of Metal, It is Not Fun)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Concentration cell

A

Type of galvanic cell. Spontaneous. Chemically identical electrodes. Curren generated is as a fiction of a concentration gradient.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Rechargeable batteries

A

Can function as high galvanic and electrolytic cell.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Positive and negative of galvanic cells

A

Anode- negative

Cathode- positive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Positive and negative of electrolytic cells

A

Anode- positive
Cathode- negative
Because it requires an external source to reverse the charge of an electrolytic cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Reduction potentials for galvanic cells

A

More + reduction potential = cathode. Less + reduction potential = anode.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Reduction potentials for electrolytic cells

A

More + reduction potential = anode. Less + reduction potential = cathode.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Solving for emf based on reduction potentials

A

Ecell = Ecathode - Eanode

(-) answer means nonspontaneous thus electrolytic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Relationship between Gibbs free energy and emf

A

🔺G = -nFEcell

n- number of moles of e- exchanged

17
Q

Nerst equation (used when conditions deviate from standard conditions)

A

Ecell = Ecell -0.0592/n (log Q)

Q- reaction quotient

18
Q

Combination of 2 🔺G expressions

A

nFEcell = RTln(Keq)

19
Q

Calculating log or ln rules…

A

If the log is…
+ when greater than 1
- when less than 1
0 when equal to 1

20
Q

Change in Gibbs free energy of an electrochemical cell with varying concentrations

A

🔺G = 🔺G* + RT ln(Q)

🔺G* under standard conditions

21
Q

Electrolysis

A

External voltage source drives this nonspontaneous oxidation-reduction reaction

22
Q

What is the only thing E*cell is dependent on?

A

The identity of the electrodes

23
Q

What is reduced in electrochemical cells?

A

Cathode

24
Q

What is reduced in galvanic cells?

A

More positive reduction potential