Oxidation-reduction

Question 1

Reduces other species by losing electrons

Answer 1

reducing agent

Question 2

Oxidizes other species by gaining electrons

Answer 2

oxidizing agent

Question 3

Common oxidizing agents are __, __, __ and _____, which favor gaining an electron to have a full octet

Answer 3

O2, O3, H2SO4, halogens

Question 4

Common reducing agents are __, __, __ and ___ __ which favor losing an electron to have a full octet

Answer 4

H2, Fe, Zn, alkali metals

Question 5

the total number of electrons that an atoms gains or loses electrons when a bond is formed

Answer 5

oxidation states

Question 6

atoms in their ___ ___ have an oxidation number of zero. Oxidation numbers for atoms in ____ ___ are equal to their charge. __ is always assigned an oxidation number of -1, oxygen is often ___, and hydrogen is usually ___

Answer 6

elemental state, monoatomic ions, fluorine, +2, +1

Question 7

__ ___ often have an oxidation number of +1, and ___ __ ____ often have an oxidation number of +2

Answer 7

alkali metals, alkaline earth metals

Question 8

Exceptions are, if oxygen is in a ___, (___), it’s oxidation number is -1. If oxygen is bonded to fluorine the oxidation number of oxygen is ____. If hydrogen is part of a __ ___, the oxidation number is ____

Answer 8

peroxide, H2O2, +1, metal hydride, -1

Question 9

To balance the redox reaction under acidic conditions, each ___ reaction must be written and firstly all atoms must be balanced other than __ and ___. Then balance the number of oxygen atoms by adding the same number of __ molecules to the opposite side. Balance the hydrogen atoms by adding __ to the opposite side. Balance the charges by adding ____. Multiply the equations to make sure each half reaction has the same number of ___, then add them together and cancel common terms

Answer 9

half, oxygen hydrogen, H2O, H+, electrons, electrons

Question 10

In basic reactions the H+ must be balanced with ___ and then combined to create ____.

Answer 10

OH-, H2O

Question 11

Electrochemical cells convert ___ energy to ___ energy or vice versa using __ __ and the movement of ___

Answer 11

chemical energy, electrical, redox reactions, electrons

Question 12

Electrons always flow from the ___ to the ___

Answer 12

anode, cathode

Question 13

energy produced from chemical reactions from energy stored in the bonds of atoms and molecules

Answer 13

chemical energy

Question 14

energy produced from the flow of electrons

Answer 14

electrical energy

Question 15

a cell that is spontaneous like a battery

Answer 15

galvanic (voltaic) cell

Question 16

a non spontaneous cell like a rechargeable battery

Answer 16

electrolytic cell

Question 17

In a galvanic cell, due to a chemical reaction in the battery ____, the __ builds up an excess of ___. Then electrons flow from the __ to the ___ spontaneously through the wire to produce ___. This process converts __ energy to ___ energy

Answer 17

electrolyte, anode, electrons, anode, cathode, electricity, chemical, electrical

Question 18

Galvanic cells have a delta G ___ 0, the electrons move from the anode (__) to the cathode (__), they turn __ energy to ___ energy, do not require an external __ ___, have oxidation at the __ and reduction at the ___, and have a Ecell __ 0

Answer 18

< -, +, chemical, electrical, power source, anode, cathode, >

Question 19

The salt bridge is a tube filled with __ ____. The anions from it flow towards the ____, which balances the increasing cations in the solution, and the ____ from the salt bridge flow to the ____ which balances the decreasing cations in the solution. As the reaction progresses the size of the ____ electrode increases, and the __ electrode decreases

Answer 19

nonreactive electrolytes, anode, cations, cathode, copper, zinc

Question 20

Spontaneous redox reactions ___ electrons released by the anode, causing the battery to __ __ and not produce electricity

Answer 20

deplete, lose power

Question 21

Electrolytic cells use a __ __ to force electrons to flow ___ in order to ensure the battery can be fully charged

Answer 21

power source, non spontaneously

Question 22

In electrolytic cells, the delta g is __ 0, the electrons flow from the anode (__) to the cathode (__). ____ energy is converted to ____ energy, it requires an external __ __, oxidation is at the __, and reduction is at the ____, and the Ecell is __ 0

Answer 22

> , +, =, electrical, chemical, power source, anode, cathode, <

Question 23

a porous barrier is a barrier that allows for the flow of __ and ___ charges like a salt bridge. The use of one is dependent on the design and not always ___

Answer 23

ions, neutralizes, necessary

Question 24

When a power source forces the nonspontaneous movement of electrons to the cathode

Answer 24

molten electrolysis

Question 25

In ____ one metal is plated with another to cover it in a thin layer. The metal being plated is made into the ___ and is the site of____

Answer 25

electroplating, cathode, reduction

Question 26

The sum of the oxidation potential and reduction potential measured in voltage

Answer 26

Ecell

Question 27

If Ecell __ 0, the cell is spontaneous. if Ecell is ___ 0 the cell is non spontaneous

Answer 27

> , <

Question 28

Reduction potentials that are greater and more negative are stronger __ ___, weaker __ __, and want to __ electrons

Answer 28

reducing agents, oxidizing agents, lose

Question 29

The moles of the product formed in electroplating is given by ____

Answer 29

I (current) (time)/number of moles of electrons transferred (F)

Question 30

To find the change in free energy and cell potential, the following equation is used ___

Answer 30

delta G = -nFE