Activity Series & Redox Reactions

Question 1

Oxidation

Answer 1

The loss of 1 or more electrons by a substance

A- ——> A + electron
A ——> A+ + electron

Question 2

Reduction

Answer 2

The gain of 1 or more electrons by a substance

A+ + electron ——> A
A + electron ——> A-

Question 3

Oxidation number

Answer 3

Indicates whether an atom is neutral, electron-rich, or electron-poor

Question 4

An atom in its elemental state has an oxidation # of…

Answer 4

0

Question 5

An atom in a monotomic ion has an oxidation #…

Answer 5

Identical to its charge

Question 6

Hydrogen has an oxidation # of…

Answer 6

(+1) or (-1)

Question 7

Oxygen usually has an oxidation # of…

Answer 7

-2

Question 8

Halogens usually have an oxidation # of…

Answer 8

-1

Question 9

The sum of the oxidation numbers in a compound is…

Answer 9

• 0 for a neutral compound
• equal to net charge for poly atomic ion

*for finding charges of atoms your are unsure of

Question 10

Redox reactions

Answer 10

Consist of two half reactions ( one oxidation, one reduction)

Question 11

Reducing agent

Answer 11

• causes reduction
• loses 1 ore more electrons
• undergoes oxidation
• oxidation # increases

Question 12

Oxidizing agent

Answer 12

• causes oxidation
• gains 1 or more electrons
• undergoes reduction
• oxidation # decreases

Question 13

Generally, metals…

Answer 13

• are more cation-like
• have positive oxidation #’s
• are reducing agents
• lose electrons

Question 14

Generally, nonmetals…

Answer 14

• are more anion-like
• have negative oxidation #’s
• are oxidizing agents
• gain electrons

Question 15

Activity series

Answer 15

Ranks the elements in their ability to give up electrons (reducing ability) in aqueous solution

Question 16

Fe (s) + Cu2+ (aq) ——> Fe2+ (aq) + Cu (s)

Answer 16

Iron gives up 2 electrons to copper

Iron reduces copper

Question 17

React rapidly with H+ ions (acid) or liquid H2O to release H2 gas

Answer 17

-strongly reducing
Li —> (Li+) + (e-)
K—> (K+) + (e-)
Ba—> (Ba2+) + (2e-)
Ca—> (Ca2+) + (2e-)
Na—> (Na+) + (e-)

Question 18

React with H+ ions (acid) or steam to release H2 gas

Answer 18

Mg—>(Mg2+) + (2e-)
Al—> (Al3+) + (3e-)
Mn—> (Mn2+) + (2e-)
Zn—> (Zn2+) + (2e-)
Cr—> (Cr3+) + (3e-)
Fe—> (Fe2+) + (2e-)

Question 19

React with H+ ions (acid) to release H2 gas

Answer 19

Co—> (Co2+) + (2e-)
Ni—> (Ni2+) + (2e-)
Sn—> (Sn2+) + (2e-)

Question 20

The position of hydrogen indicates which elements react with acid to release H2 gas

Answer 20

H2—> (2H+) + (2e-)

Question 21

Do not react with H+ ions (acid) to release H2 gas

Answer 21

-weakly reducing
Cu—> (Cu2+) + (2e-)
Ag—> (Ag+) + (e-)
Hg—> (Hg2+) + (2e-)
Pt—> (Pt2+) + (2e-)
Au—> (Au3+) + (3e-)