Unit 4

Question 1

What is the difference in writing a charge and an oxidation state?

Answer 1

Oxidation state- +1

Charge- 1+

Question 2

What is the oxidation state of fluorine always?

Answer 2

-1

Question 3

What is the oxidation state of hydrogen when it’s bonded to a more electronegative element? A metal?

Answer 3

More electronegative- +1

Metal- -1

Question 4

What is the difference between oxidation and reduction reactions? What’s LEO GER mean?

Answer 4

Oxidation- reaction where an ion or atom increases its oxidation state
Reduction- reaction where an ion or atom decreases its oxidation state

LEO- loss of electrons= oxidation
GER- gain of electrons= reduction

Question 5

How does the number of electrons lost in an oxidation compare with the number gained in the simultaneous reduction?

Answer 5

The two number are equal

Question 6

In redox reactions, which agent is the one being reduced? The oxidizing agent or reducing agent?

Answer 6

Oxidizing agent

Question 7

What is a redox reaction?

Answer 7

A reaction where any oxidation numbers change

Ex: it is not a redox reaction if all the oxidation numbers are the same throughout

Question 8

How do we balance redox reactions in acidic conditions?

Answer 8

Start off normal then if the H and O don’t balance you balance the O’s first by adding H2O’s to the side with less O’s. Then add H+ to the side needed to balance H

Question 9

How do you balance redox reactions in basic conditions?

Answer 9

Balance the equation like acidic condition, then if you used an H+ you add an OH- to both sides equal to the amount of H+’s you used

Question 10

What determines the strength of oxidizing and reducing agents?

Answer 10

Their abilities to give and take electrons

How easily

Question 11

How does the strength of oxidizing/reducing agents table work in terms of order?

Answer 11

For example, any reducing agent can be oxidized by the oxidizer below it
Any oxidizing agent can be reduced by the reducer below it

Question 12

What are the products when hydrogen peroxide decomposes?

Answer 12

Oxygen and water

Question 13

What is a voltaic electrochemical cell?

Answer 13

Also called a galvanic cell that spontaneously converts chemically stored potential energy into moving electrons through a redox reaction

Question 14

Example of voltaic cells?

Answer 14

Battery

Question 15

What is produced when reactants in spontaneous energy releasing redox reactions are in direct contact? (Voltaic Cells)

Answer 15

Heat

Question 16

What is red cat and an ox mean?

Answer 16

Red cat= reduction-cathode

An ox= oxidation-anode

Question 17

What are electrolytic cells? Examples?

Answer 17

Cells where electricity is used to reverse a spontaneous redox process
It’s non spontaneous

Ex: recharging battery or electroplating

Question 18

What is a voltaic wet cell?

Answer 18

The two beakers diagram with the salt bridge and the two electrodes in the beakers

Question 19

What is the voltage of a voltaic cell by the E0 values determined by?

Answer 19

Half reactions of the cathode and anode

Question 20

What is electroplating?

Answer 20

Normally a voltaic cell disappears an anode and grow the cathode but electroplating reverses this by changing the anode to a cathode

Question 21

What is the object plated to in an electroplating cell?

Answer 21

Cathode

Question 22

What is the electrode potential equation?

Answer 22

E^o cell= E^o cathode - E^o anode

Question 23

What does the values of E^o have to be for a reaction to be either spontaneous or not spontaneous?

Answer 23

Spontaneous- E^o cell is positive

Not spontaneous- E^o cell is negative

Question 24

How can we use the table of standard reduction potentials to find which elements in an equation are oxidized or reduced?

Answer 24

More positive potential on chart means it’s a cathode which means it’s reduced.
More negative potential on chart means it’s a anode which means it’s oxidized