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)

utilize redox reactions (transfer of electrons)

Question 2

2 fundamental types of electrochemical cells

Answer 2

galvanic (voltaic) cells

electrolytic cells

concentration 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 charge in an electrolytic cell?

Answer 13

anode to cathode

electrons ALWAYS flow anode to cathode

Question 14

what are the 2 separate compartment of galvanic cells called

Answer 14

half-cells

Question 15

Salt bridge

Answer 15

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 16

cell diagram

Answer 16

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

Question 17

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

Answer 17

anode to cathode

Question 18

Standard Reduction Potential

Answer 18

describes each elements natural tendency to either gain or lose electrons

Question 19

positive Standard Reduction Potential

Answer 19

element sponteneously GAINS electrons

wants to be reduced

Question 21

negative Standard Reduction Potential

Answer 21

element sponteneously LOSES electrons

does NOT want to be reduced

Question 21

Standard Reduction Potential of the entire cell

Answer 21

Question 22

when SRP is positive

Answer 22

delta G is negative (spontaneous!)

Question 23

in galvanic cells, the anode is…

charge

Answer 23

negatively charged

anode loses electrons… electrons move away from negative charge

Question 24

in galvanic cells, the cathode is…

charge

Answer 24

positively charged

cathode gains electrons… electrons move toward the positive charge