ch8: production of chemicals by electrolysis

Question 1

what sort of reaction is electrolysis

Answer 1

non-spontaneous (forced) reaction

Question 2

what sort of energy conversion occurs in an electrolytic cell?

Answer 2

electrical energy is converted into chemical energy

Question 3

what are the polarity of electrodes in electrolysis?

Answer 3

• anode is positive
• cathode is negative

Question 4

similarities between galvanic and electrolytic cells

Answer 4

• oxidation always occurs at the anode
• reduction always occurs at the cathode
• electron flows from anode to cathode
• strongest oxidant will react with the strongest reductant

Question 5

how to determine the non-spontaneous reaction from the electrochemical series?

Answer 5

smallest gap between oxidants and reductants

Question 6

what is a molten liquid?

Answer 6

a molten liquid is formed when heat is applied to a solid to form a liquid.

Question 7

how can you tell which electrode is the positive and negative in an electrolytic cell?

Answer 7

the positive electrode will be connected to the positive terminal and the negative electrode will be connected to the negative terminal.

Question 8

why do the products of an electrolytic cell have to be kept apart?

Answer 8

because they will react spontaneously.

Question 9

differences between galvanic and electrolytic cells?

Answer 9

galvanic cells
- produce electricity
- react spontaneously
- chemical energy -> electrical energy
- anode is neg, cathode is pos
electrolytic cells
- consume electricity
- non-spontaneous reaction
- electrical energy -> chemical energy
- anode is pos, cathode is neg

Question 10

faraday’s first law of electrolysis

Answer 10

Q=It
where Q is charge (coulombs)
I is current (amps)
t is time (seconds)

Question 11

faraday’s second law of electrolysis

Answer 11

Q=n(e-)*F
where Q is charge(coulombs)
n(e-) is the moles of an electron
F is faraday’s constant (96500)