Assignment 10: Redox

Question 1

Redox

Answer 1

Oxidation and Reduction (transfer of electrons from one place to another)

Question 2

Oxidation

Answer 2

Loss of electrons A —> A⁺² + 2e^-

Question 3

Reduction

Answer 3

Gain of electrons Cu⁺² + 2e^- —> Cu

Question 4

OILRIG

Answer 4

Oxidation Is Loss Reduction Is Gain

Question 5

anode -

Answer 5

• oxidation

Question 6

cathode -

Answer 6

• reduction

Question 7

Reduction Potential Table

Answer 7

A table showing the measure, in volts, of how much the electons flow relative to a standard (SHE: standard hydrogen electrode)

Question 8

SHE

Answer 8

Standard Hydrogen Electrode 2H⁺ + 2e^- —> H₂

Question 9

spontaneous

Answer 9

positive voltage

Question 10

non-spontaneous

Answer 10

negative voltage

Question 11

Reduction Potential Lab

Answer 11

Goal: create your own reduction potential table with lead as standard (0).

• Cu wants to reduce more than Ni, Pb or Zn
• Zn wants to oxidize more than Ni, Pb, Cu

Question 12

Oxidation Number

Answer 12

Charge on each atom, not the whole molecule

Question 13

Double Replacement Reaction

Answer 13

Never a Redox Reaction

Question 14

Oxidation Number for Diatomic Elements

Answer 14

Always 0 because they are sharing electrons with themselves

Question 15

Finding Oxidation Number

Answer 15

Look at electronegativity first (either least or more electronegative)

Question 16

Recharging a Battery

Answer 16

In order to recharge, the electrons must be forced to move in the opposite direction

Question 17

1 mole e^- (electrons) =

Answer 17

96500 coulombs

Question 18

1 amp =

Answer 18

1 coulomb/sec

Question 19

Direct Current (DC)

Answer 19

electrons flow in one direction only

Question 20

Alternating Current (AC)

Answer 20

electrons flow in both directions, 60hz cutten switches direction in wall electrics

Question 21

Balancing Redox Reactions

Answer 21

**remember to balance charge**

two ways:

1) oxidation number method
2) half reaction method

Question 22

Oxidation Number Method

Answer 22

1) find the oxidation number of each atom
2) determine what is oxidizing and what is reducing and by how many electrons
3) multiply the coefficient that makes the number of electron lossed and gained equal
4) balance other atoms if needed (if in an aqueous solution, add H2O, H+, OH- to balance)
5) check balance of atoms and charge

Question 23

Half Reaction Method

Answer 23

1) determine what’s oxidized and what’s reduced
2) write them as two separate half-reactions
3) balance each separately for both charge and atoms (if in an aqueous solution, add H2O, H+, OH- to balance)
4) multiply each by the coefficient that allows electrons lost and gained to be equal
5) add and simplify
6) check balance of atoms and charge

Question 24

Types of Decay

Answer 24

alpha ⁴₂α

beta ⁰_-1β

Question 25

fission

Answer 25

larger nuclei splitting into smaller nuclei

• radioactive particles

Question 26

fissile

Answer 26

capable of undergoing fission

Question 27

fusion

Answer 27

smaller nuclei combining into larger nuclei