12.1 Electrochemical Cells

Question 1

Electrochemical cells

Answer 1

convert between electrical and chemical energies

utilizes redox reactions (transfer of electrons) to harness electricity (flow of electrons)

(either generate electrical energy from chemical reactions or generate chemical energy from electricity)

Question 2

2 fundamental types of electrochemical cells

Answer 2

galvanic (voltaic) cells

electrolytic cells

3rd: concentration cells (for another time?)

Question 3

which electrochemical cell types house non spontaneous reactions

Answer 3

electrolytic cells

Question 4

which electrochemical cell types house spontaneous reactions

Answer 4

galvanic (voltaic) and concentration cells

Question 5

2 types of electrodes

Answer 5

anode: the electrode where oxidation occurs

cathode: the electrode where reduction occurs

An Ox; Red Cat

Question 6

anode

Answer 6

electrode where oxidation occurs

Question 7

cathode

Answer 7

electrode where reduction occurs

Question 8

purpose of galvanic cells

Answer 8

to collect electrical energy from a spontaneous chemical reaction

Question 9

purpose of electrolytic cells

Answer 9

to convert electrical energy into chemical energy

a RECHARBEABLE battery

plugging phone into wall to recharge the battery

Question 10

main difference between galvanic cell and electrolytic cell?

Answer 10

flow of electrons is reversed!!

we are putting the electrons back into the cathode so we can redo the chemical reaction and harness more energy later

Question 11

which direction is the flow of electrons in a galvanic cell?

Answer 11

anode to cathode

spontaneous flow of electrons… going the the place of reduction

Question 12

does the flow from anode to cathode change between the 2 cell types?

Answer 12

NO! anode will always be oxidized and cathode will always be reduced!!

what changes is which chemical species is the cathode/anode

Question 13

which direction is the flow of electrons in an electrolytic cell?

Answer 13

anode to cathode

electrons ALWAYS flow anode to cathode

Question 14

which direction is the flow of charge in an electrochemical cell?

Answer 14

cathode to anode

the flow of charge is always opposite th flow of electrons

Question 15

what are the 2 separate compartment of galvanic cells called

Answer 15

half-cells

Question 16

Salt bridge

Answer 16

the structure which connects the 2 solutions; consists of an inert salt/electrolyte

allows anions and cations to flow into either half-cell to balance newly generated charges so the reaction can continue

Question 17

[…] is the shorthand notation used to represent the components of a voltaic cell without having to draw a picture of the whole things

Answer 17

Cell Notation / Cell Diagram is the shorthand notation used to represent the components of a voltaic cell without having to draw a picture of the whole things

Question 18

cell diagram

Answer 18

Anode | anode sol’n (concentration) || cathode sol’n (concentration) | cathode

Question 19

electrons always flow from —– to —— in ALL electrochemical cells

Answer 19

anode to cathode

Question 20

Standard Reduction Potential

Answer 20

describes each elements natural tendency to either gain or lose electrons

Question 21

positive Standard Reduction Potential

Answer 21

element sponteneously GAINS electrons

wants to be reduced

Question 22

negative Standard Reduction Potential

Answer 22

element sponteneously LOSES electrons

does NOT want to be reduced

Question 23

Standard Reduction Potential of the entire cell

Answer 23

Question 24

when SRP is positive

Answer 24

delta G is negative (spontaneous!)

Question 25

in galvanic cells, the anode is…

charge

Answer 25

negatively charged

anode loses electrons… electrons move away from negative charge

Question 26

in galvanic cells, the cathode is…

charge

Answer 26

positively charged

cathode gains electrons… electrons move toward the positive charge

Question 27

the standard cell potential is…

Answer 27

the voltage difference between the anode and cathode

Question 28

In a galvanic/voltaic cell, the standard cell potential is [positive/negative]

Answer 28

positive

Question 29

In an electrolyric cell, the standard cell potential is [positive/negative]

Answer 29

negative

Question 30

Cell potential energy (E cell)

Answer 30

a measure of the spontaneity of the reaction

Question 31

the larger the cell potential, the more …

Answer 31

… work we get out of the cell