Oxidation Reduction Reactions

Question 1

What was the term oxidation originally used to describe?

Answer 1

Chemical reactions involving O2

Question 2

True or False: Some redox reactions involve the transfer of electrons between reactant species to yield ionic products

Answer 2

True

Question 3

What is a half reaction?

Answer 3

An equation that shows whether each reactant loses or gains electrons in a reaction

Question 4

What does oxidation symbolize?

Answer 4

The loss of electrons

Question 5

What does reduction symbolize?

Answer 5

The gain of electrons

Question 6

What does it mean to oxidized?

Answer 6

One of the reactants is losing an electron for the other to undergo reduction (gaining said lost electron)

Question 7

What is a reducing agent/reductant?

Answer 7

Species that is oxidized

Question 8

What is an oxidizing agent/oxidant?

Answer 8

Species that is reduced

Question 9

What is the oxidation number/oxidation state of an element?

Answer 9

Of an element in a compound is the charge its atoms would possess if the compound were ionic

Question 10

What type of bonds do oxidation numbers/oxidation states refer to?

Answer 10

Covalent compounds

Question 11

What guidelines are used to assign oxidation numbers to each element in a molecule or ion?

Answer 11

1. The oxidation number of an atom in an elemental substance is zero.
2. The oxidation number of a monatomic ion is equal to the ion’s charge.
3. Oxidation numbers for common nonmetals are usually assigned as follows:
   Hydrogen: +1 when combined with nonmetals, −1 when combined with metals
   Oxygen: −2 in most compounds, sometimes −1 (so-called peroxides, O22−), very rarely -½ (so-called superoxides, O2−), positive values when combined with F (values vary)
   Halogens: −1 for F always, −1 for other halogens except when combined with oxygen or other halogens (positive oxidation numbers in these cases, varying values)
4. The sum of oxidation numbers for all atoms in a molecule or polyatomic ion equals the charge on the molecule or ion.

Question 12

The proper convention to write the oxidation number is

A. The same as reporting the charge sequence of an element
B. The reverse of reporting the charge sequence of an element

Answer 12

B

Question 13

What are oxidation-reduction (redox) reactions?

Answer 13

Those in which one or more elements involved undergo a change in oxidation number

Question 14

What does a oxidation result in?

Answer 14

An increase in oxidation number

Question 15

What does a reduction result in?

Answer 15

A decrease in oxidation number

Question 16

True or False: Combustion reactions are subclasses of redox reactions

Answer 16

True

Question 17

What is the reductant of a combustion reaction called?

Answer 17

A fuel

Question 18

What is a single displacement (replacement) reaction?

Answer 18

Redox reactions in which an ion in solution is displaced (or replaced) via the oxidation of a metallic element

Question 19

Under what circumstances do single-replacement reactions occur?

Answer 19

Single-replacement reactions only occur when the element that is doing the replacing is more reactive than the element that is being replaced

Question 20

What is the activity series?

Answer 20

A list of elements in decreasing order of their reactivity

Question 21

For a single-replacement reaction, a given element is capable of doing what under what conditions?

Answer 21

A given element is capable of replacing an element that is below it in the activity series