CHEM 120 Week 5 Oxidation Reduction Questions and Answers- Chamberlain College Atlanta
WEEK 5
Oxidation-Reduction
1. Redox reactions involve a transfer
... [Show More] of:
a. Neutrons
b. Nucleons
c. Protons
d. Electrons
Electrons are exchanged in a redox reaction.
2. If iron reacts with oxygen gas in the reaction 2 Fe(s) + O2(g) → 2 FeO(s), what is
oxidized in this reaction?
a. O2
b. No oxidation is occurring here
c. FeO
d. Fe
In a redox reaction, the atom being oxidized often accepts an oxygen atom. Iron is oxidized
in this reaction as the Fe is joined to an oxygen.
3. Oxidation involves the loss of electrons while reduction involves the gain of
electrons. Consider a reaction where a Li+ is converted into Li. Do you think that
this Lithium atom gained or lost an electron?
a. gained electron
b. lost electron
As electrons are lost, charge becomes more positive and we call this process oxidation. As
electrons are gained, the charge on an atom becomes more negative and is called reduction.
Li+ has to gain an electron to become Li (more negative).
4. In the following reactions, indicate if the species is oxidized or reduced:
Mg2+ becomes Mg --- Reduced
Oxidized, Reduced
O becomes O2- --- Reduced
Oxidized, Reduced
Fe2+ becomes Fe3+ --- Oxidized
Oxidized, Reduced
F becomes F- --- Reduced
Oxidized, Reduced
Cu becomes Cu+ --- Oxidized
Oxidized, Reduced
H becomes H+ --- Oxidized
Oxidized, Reduced
We can tell if electrons were lost or gained based on the change of charge.
Mg2+ becomes Mg = Reduced
O becomes O2- = Reduced
Fe2+ becomes Fe3+ = Oxidized
F becomes F- = Reduced
Cu becomes Cu+ = Oxidized
H becomes H+ = Oxidized
5. Choose the correct agent in each of these reactions: --- O2(g)
Mg(s) + O2(g) → MgO Select the oxidizing agent:
Mg(s), O2(g), MgO
CuO(s) + H2(g) → Cu(s) + H2O(g) Select the reducing agent: --- H2(g)
CuO(s), H2(g), Cu(s), H2O(g)
2 Na(s) + Cl2(g) → NaCl(s) Select the reducing agent: --- 2 Na(s)
2 Na(s), Cl2(g), NaCl(s)
You can determine oxidizing and reducing agents based on the change in charge.
Mg(s) + O2(g) → MgO The oxidizing agent is O2(g)
CuO(s) + H2(g) → Cu(s) + H2O(g) The reducing agent is H2(g)
2 Na(s) + Cl2(g) → NaCl(s) The reducing agent is 2 Na(s)
6. If a species accepts electrons from another reactant in a chemical reaction, this
species is: (select all that apply)
a. Oxidizing agent
b. Reducing agent
c. Being oxidized
d. Being reduced
We use the transfer of electrons to determine the redox character of the reactants.
Remember, LEO goes GER. Also note, reducing agents reduce another species in a
chemical reaction, while oxidizing agents oxidize another species in a chemical reaction. In
this case, if a species accepts electrons from another it is being reduced.
7. Which metal is being oxidized based on the reaction? Cu(s) + Ag+(aq) → Cu+(aq) +
Ag(s)
a. Cu(s)
b. Ag+(aq)
c. Cu+(aq)
d. Ag(s)
Loss of electrons is oxidation. Since electrons have a -1 charge, losing electrons leads to
more positive charges while gaining electrons leads to more negative charges. In this case,
Cu loses an electrons (becomes more positive) and so is the one being oxidized.
8. What would be the oxidizing agent in the reaction 2 Ag(s) + O2(g) → Ag2O(s)
a. Ag(s)
b. O2(g)
c. Ag2O(s)
d. This is not a redox reaction
Oxygen is often an oxidizing agent.
9. An important reaction in metabolism involves NAD+. In the reaction, what
compound would be considered the oxidizing agent: NAD+ + 2 H → NADH + H+
a. NAD+
b. H
c. NADH
d. H+
Oxidizing agents accept electrons, which in this case is NAD+
Organic Chemistry- Hydrocarbons
10. Two carbon atoms are bonded directly together, and each have one single bond to a
hydrogen. This will require three more bond(s) to meet the bonding requirements of
carbon, and will be accomplished by a triple bond.
One, two, three, four
Single, double, triple, quadruple
Because each carbon has one bond, it will need three other bonds to meet the four bond
requirement of carbon. This will be accomplished by a triple bond.
11. Match the correct root (prefix) to the number of carbons in the chain
1 --- Meth2 --- Eth-
3 --- Prop4 --- But6 --- Hex8 --- OctOct-, Non-, Eth-, Prop-, Dec-, Pent-, Hex-, But-, Hept-, MethThe prefix for 1 carbon is meth-; for 2 is eth-; for 3 is prop-; for 4 is but-; for six is hex-; for
eight is oct-.
12. How many carbons are in butane, often used in cooking fuel?
a. 1
b. 2
c. 3
d. 4
The root “but” tells us there are four carbons, and the suffix “-ane” tells us this carbon
chain contains only carbon-carbon single bonds.
13. How many carbons are in methane, a common greenhouse gas expelled from cattle?
a. 1
b. 2
c. 3
d. 4
The root “meth” tell us there is only one carbon in this carbon chain.
The carbon is typed first and its attached atoms are typed immediately following. We know
in organic chemistry each carbon will have four total bonds and will bond in carbon chains.
When there are carbon-carbon single bonds, there will be three hydrogens attached to
carbons on the end and two on carbons in the middle of molecules. For double or triple
bonds, there will be fewer than three hydrogens on the end and fewer than two hydrogens
attached to middle carbons. Each additional bond will remove two H: one from each
carbon where the double bond is found.
14. Which of the following will show the difference in structure between isopropanol
(rubbing alcohol) and propanol? Select all that apply.
a. Condensed structural formula
b. Molecular weight
c. Extended structural formula
d. Molecular formula
The way to determine a difference in structure is through a structural formula such as the
extended structural formula, or the condensed structural formula. Molecular formula or
molecular mass will be identical for isomers, which have different structures but identical
formulas.
15. Which of the following contains triple bonds?
a. butene
b. butane, butene, butyne
c. butane
d. butyne
Hydrocarbons containing triple bonds are called alkynes, and will have the suffix ‘-yne’ in
the name.
16. Determine if the hydrocarbon is saturated or unsaturated.
Alkene --- unsaturated
Saturated, unsaturated
Alkyne --- unsaturated
saturated
unsaturated
Alkane --- Saturated
saturated
unsaturated
Alkanes are saturated whereas alkenes and alkynes are unsaturated.
Benzene and cyclohexane both are hexagons; benzene will have double bonds every other
carbon, whereas cyclohexane will have only single bonds. Cyclopentane is a pentagon with
carbon-carbon single bonds. Naphthalene is a bi-cyclic structure that looks like two
benzene rings fused together.
Cyclic hydrocarbons are saturated and include cyclohexane and cyclopentane. Aromatic
hydrocarbons are unsaturated, and include phenol and benzene.
17. Which of the following contains double bonds?
a. CH2CHCH2CH2CH3
b. hexyne
c. methane
d. ethene
e. CH3CH2CH2CH3
Hydrocarbons containing double bonds will have the suffix -ene in the name, and will have
one fewer hydrogen in the condensed structural formula compared to an alkane: the
alkenes will have CH2 on end carbons and/or CH on middle carbons.
18. Drag the compound to its correct classification: cyclic hydrocarbon or aromatic
hydrocarbon.
Aromatic Hydrocarbon --- Benzene, Phenol
Cyclic Hydrocarbon --- Cycloheptane, Cyclopentane
Cycloheptane, Benzene, Phenol, Cyclopentane
Cyclic compounds are named with the prefix “cylco-” such as cycloheptane or
cyclopentane. Aromatic compounds include benzene, phenol, and naphthalene.
19. Which of the following is an unsaturated hydrocarbon containing seven carbons?
a. heptene
b. hexane
c. mutane
d. benzene
e. pentene
The root for seven is "hept-" and the unsaturated hydrocarbon will be an alkene or alkyne.
The name heptene shows it is an unsaturated chain of seven carbons.
20. Determine if the compound is saturated or unsaturated:
Benzene --- Unsaturated
Saturated, Unsaturated
Propyne --- Unsaturated
Saturated, Unsaturated
Methane --- Saturated
Saturated, Unsaturated
Propane --- Saturated
Saturated, Unsaturated
Saturated hydrocarbons include the alkanes. These have names that end in the –ane suffix.
Unsaturated hydrocarbons include alkenes and alkynes. These have names that end in the
–ene or –yne suffixes, respectively.
21. The compound with a condensed structure of CH3CCCH2CH3 has 5 carbons and has a
triple bond. The name will be pent yne.
1, 2, 3, 4, 5
single, double, triple
meth, eth, but, prop pent
ane, ene, yne
CH3CCCH2CH3 has five carbons total, meaning the root is pent. This has triple bonding
because two middle carbons are missing two H each, giving the suffix yne. The name will be
pentyne.
22. Choose the correct condensed structure from the name: hexene.
a. CHCCH2CH3
b. CH3CHCHCH2CH3
c. CH3CH2CHCHCH2CH3
d. CH3CH2CH2CH2CH2CH3
Hexene will have six carbons and a double bond, from the “hex” root meaning six and the –
ene suffix. The double bond in a condensed structure has one less H on each of the involved
carbons.
CH2CH2 will have a double bond to fulfill the four bond requirement of carbon.
This molecule contains four carbons and one double bond. It’s name is butene, and its
condensed structural formula will follow the extended structural formula: CH3CHCHCH3
23. Due to its electron configuration and valence shell electrons, carbon can form 4 bonds,
nitrogen can form 3 bonds, and oxygen can form 2 bonds.
1, 2, 3, 4, 5
1, 2, 3, 4, 5
1, 2, 3 ,4, 5
Carbon will form four bonds, nitrogen will form three, and oxygen will form two bonds.
24. Carbons can form carbon-carbon links, also known as __________, that can be linear or
cyclic.
a. carbon connections
b. carbon chains
c. carbon bridges
d. triple bonds
e. root number
Carbon has the unique property to bond to itself, resulting in carbon chains.
Organic Chemistry- Functional Groups
25. Choose the correct number of total bonds for each of the atoms below:
Carbon ---4
1, 2, 3, 4, 5
Oxygen ---2
1, 2, 3, 4, 5
Nitrogen ---3
1, 2, 3, 4, 5
Hydrogen ---1
1, 2, 3, 4, 5
Based on the number of unpaired valence electrons, Carbon will require 4 bonds, Oxygen
requires 2 bonds, Nitrogen requires 3 bonds, and Hydrogen requires 1 bond.
For naming, remember to first name the hydrocarbon as if it were an alkane, drop the –e,
and then add an –ol ending. Isomers have a different arrangement, so Isopropanol will
have the –OH located in the middle rather than on the end carbon. In propanol, the –OH
group is located on the end carbon.
Aldehydes are carbonyls on the beginning or end carbon. Ketones are carbonyls on a
middle compound. Note, the minimum number of carbons to have a ketone is three because
that is the first opportunity to have a middle carbon.
26. Match the structural formula to the correct name:
CH3CH2CHO --- propanal
CH3COCH2CH3 --- butanone
CH3CHOHCH2CH3 --- ethanal
CH3CHO --- butanol
CH3COCH3 --- propanone
CH3CH2OH --- ethanal
Propanal, Butanone, Ethanal, Butanol, Ethanol, Butanal, Propanone, Ethanone
CH3CH2CHO= Three carbons and -CHO give the name propanal
CH3COCH2CH3= Four carbons and –CO- in the middle give the name butanone
CH3CHOHCH2CH3= Four carbons and –OH in the middle (shown as CHOH in the
structural formula) give the name butanol
CH3CHO= Two carbons and -CHO on the end give then name ethanal
CH3COCH3= Three carbons and –CO- in the middle give the name propanone
CH3CH2OH= Two carbons and –OH on the end give the name ethanol
27. Which of the following is a carboxylic acid?
a. CH3CH2COOH
b. CH3CHOHCH3
c. CH3CH2CHO
d. CH3CH2COCH3
The carboxylic acid is identified by –COOH in the condensed structural formula.
CH3CH2COOH has this group.
Consider the number of carbons in each chain when choosing, and remember that water is
a product of this reaction. The resulting ester is from propanoic acid and butanol due to its
final structure: the acid chain contains two oxygens, the alcohol chain contains only one
oxygen.
+ →
+
28. Match the structural formula to the correct name.
Isopentanol --- CH3CH2COOCH2CH3
pentanoic acid --- CH3CH2CH2CH2COOH
ethyl propanoate --- CH3CH2OCH2CH2CH3
Pentanone --- CH3CHOHCH2CH2CH3
ethyl propyl ether --- CH3COCH2CH2CH3
CH3CHOHCH2CH2CH3, CH3CH2COOCH2CH3 , CH3COCH2CH2CH3
CH3CH2CH2CH2COOH, CH3CH2OCH2CH2CH3
CH3CH2COOCH2CH3 = This compound has an ester group; the alcohol (ethanol) is
named first, followed by the acid (propanoic acid). The name is ethyl propanoate for the
ester.
CH3CH2CH2CH2COOH = This compound has five carbons and a carboxylic acid
functional group. Its name is pentanoic acid
CH3CH2OCH2CH2CH3 = This compound has an ether functional group. The chains
contain two carbons (eth) and three carbons (prop). Arranging the chains alphabetically,
the name will be ethyl propyl ether
CH3CHOHCH2CH2CH3 = This compound contains an alcohol in the middle of a fivecarbon chain, and is named isopentanol
CH3COCH2CH2CH3 = This compound is a ketone with 5 carbons, and its name is
pentanone.
29. Which of the following is the correct name for this halocarbon: CH3CH2F
a. difluoroethane
b. monofluoroethane
c. difluoromethane
d. fluoroethane
This structure has two carbons and one fluorine, so the name is fluoroethane.
Use the base name of the compound along with a prefix in front of the halogen name
showing how many halogens you have incorporated. (Eg. di for 2, tri for 3, etc).
30. What is the name for this molecule: CH3CH2CH2NH2
a. propylamine
b. butyl amine
c. methylamine
d. ethyl amine
This structure has three carbons and an amine group. The name is propyl amine.
31. What is the name for this molecule: CH3CH2CH2CH2CH2CH2NH2
a. heptyl amine
b. hexyl amine
c. propylamine
d. pentylamine
This structure has six carbons and an amine group. The name is hexyl amine.
32. Match the function to the compound:
Nail polish remover --- Propanone
Preservative for biological tissue --- Methanal
Lighter and torch fuel --- Butane
Characteristic component of vinegar --- Ethanoic acid
Important organic solvent, formerly used as an anesthetic --- Diethyl ether
Component of butt --- Butanoic acid
Sterilization, also consumed as an intoxicant, commonly found in hand sanitizer --- Butanoic
acid
Fruity flavoring agent --- Methyl butanoate
Methyl butanoate, Methanal, Diethyl ether, Butane, Ethanoic acid, Butanoic acid, Ethanol,
Propanone
Propanone= Nail polish remover
Methanal= Preservative for biological tissue
Butane= Lighter and torch fuel
Ethanoic acid= Characteristic component of vinegar
Diethyl ether= Important organic solvent, formerly used as an anesthetic
Butanoic acid= Component of butter
Butanoic acid = Sterilization, also consumed as an intoxicant, commonly found in hand
sanitizer
Methyl butanoate= Fruity flavoring agent
Match the function to the organic compound.
33. Used to remove permanent marker and as a household disinfectant
Smells nice, perfume ---
Fuel --- Propane
Vinegar --- Ethanoic acid
Propane
Octyl ethanoate
Propane
Ethanoic acid
Propane is saturated hydrocarbon used as a fuel. Octyl ethanoate is an ester that smells
nice and is used for perfumes. Isopropyl alcohol, also known as rubbing alcohol, is used as
a household disinfectant. Ethanoic acid is another name for vinegar.
34. What functional group is shown here: CH3COCH3
a. ether
b. ketone
c. alcohol
d. carboxylic acid
e. aldehyde
The –CO- in CH3COCH3 shows this is a ketone.
35. What functional group is shown here: CH3CHOHCH3
a. alcohol
b. aldehyde
c. ketone
d. ether
e. carboxylic acid
The -OH in CH3CHOHCH3shows this is an alcohol
36. What functional group is shown here: CH3CH2CHO
a. carboxylic acid
b. ketone
c. alcohol
d. ether
e. aldehyde
The –CHO in CH3CH2CHO shows this is an aldehyde.
37. What functional group is shown here: CH3CH2COOH
a. alcohol
b. ketone
c. ether
d. aldehyde
e. carboxylic acid
The –COOH in CH3CH2COOH shows this is a carboxylic acid.
38. Name this compound: CH3COCH2CH2CH3
a. pentanol
b. pentanal
c. pentanone
d. propyl ethanoate
e. ethyl propyl ether
Group = ketone. Chain = 5 carbons. Name = pentanone
39. Name this compound: CH3CH2CH2CHO
a. butanal
b. butanone
c. butanoic acid
d. butanol
e. butyl methyl ether
Group = aldehyde. Chain = 4 carbons. Name = butanal
40. Name this compound: CH3CH2OCH2CH2CH2CH3
a. hexanoic acid
b. hexanol
c. butyl ethyl ether
d. hexanone
e. butyl ethanoate
Chain = 4 carbons; But- prefix. Group= Ether. Name= Butyl Ethyl Ether
41. Name this compound:
a. ethanoic acid
b. ethyl ether
c. ethyl amine
d. ethane
e. methyl amine
Group = amine. Chain = 2 carbons. Name = ethyl amine.
42. What functional group is shown:
a. alcohol
b. ether
c. ketone
d. ester
This is an ether
43. What is the name of the molecule shown:
a. butanone
b. methyl propanoate
c. methyl propyl ether
d. propyl methanoate
This is named methyl propyl ether, by putting the two chains in alphabetical order.
44. Which is the correct condensed formula for difluoropropane?
a. CH2F2
b. CH2CHF2
c. CH3CH2CHF2
d. CH3CH2F2
e. CH3CH2F
The formula CH3CH2CHF2 matches the name difluoropropane.
Organic Chemistry- Applications
45. What atom do all organic molecules have in common?
a. Oxygen
b. Carbon
c. Phosphorus
d. Nitrogen
Organic molecules contain hydrocarbons as their base, and always contain carbon atoms.
46. Which type of organic molecules are relatively stable and unreactive?
a. Carboxylic acids
b. Alkanes
c. Alkenes
d. Alcohols
Alkanes are relatively stable and unreactive. They make excellent fuels for this reason.
47. Natural chemicals are safer than synthesized chemicals.
a. True
b. False
It is a common misconception that natural compounds are inherently safe. Plants are
known to make toxic chemicals, and industrial chemicals are not necessarily harmful.
Dosage is the most important consideration in determining safe or unsafe, rather than
natural and unnatural.
48. The safety of a chemical is closely related to
a. how many carbons it contains
b. how natural it is
c. how organic it is
d. the dosage in which it is used
Dosage is more important to consider than source, as natural water and natural snake
venom are both deadly in high enough amounts.
49. What is the function of carbohydrates?
a. hormones
b. energy storage
c. nonpolar and found in butter
d. component of muscles
Carbohydrates function primarily as a source of energy as well as energy storage
50. What functional group is found in amino acids?
a. alcohols
b. amines
c. alkanes
d. cyclic hydrocarbon rings
Amino acids have amine functional groups, as well as carboxylic acids.
51. Examples of steroids include
a. glucose
b. muscles
c. testosterone
d. butanoic acid
Many of the hormones in the human body are steroids including estrogen and testosterone.
52. Which of the following molecules are nonpolar?
a. proteins
b. muscles
c. cell membranes
d. butanoic acid
e. carbohydrates
The nonpolar fats will not dissolve in water, such as butter and cell membranes.
53. Match the molecule name to the application.
Preservative for biological tissue --- Methanal
Nail polish remover --- Propanone
Lighter and torch fuel --- Butane
Important organic solvent, formerly used as an anesthetic --- Diethyl ether
Component of butter --- Butanoic acid
Fruity flavoring agent --- Propanone
Sterilization, intoxicant, found in hand sanitizer --- Ethanol
Butanoic acid, Butane, Diethyl ether, Propanone, Ethanol, Methyl butanoate, Methanal
Butane= Lighter and torch fuel
Butanoic acid= Component of butter
Propanone= Nail polish remover
Propanone = Fruity flavoring agent
Ethanol= Sterilization, intoxicant, found in hand sanitizer
Methanal= Preservative for biological tissue
Diethyl ether= Important organic solvent, formerly used as an anesthetic
54. Which compound is used for tissue preservation?
a. methanal
b. alcohols
c. phenol
d. methanol
Methanal is formaldehyde, and used for tissue preservation.
55. Which compound is used for disinfection?
a. CFCs
b. ethanol
c. propanone
d. isopropyl alcohol
e. phenol
Alcohols are used for disinfection due to their toxic properties. The alcohols here have –ol
endings to the names: ethanol, isopropyl alcohol, and phenol.
56. Which compound is used for fuel?
a. propane
b. CFCs
c. phenol
d. propanone
e. butane
The alkanes are often used for fuels, such as propane and butane.
57. Which compound was used as a propellant and refrigerant until it was found that it
caused a chain reaction in the ozone layer?
a. methanal
b. isopropanol
c. CFCs
d. phenol
e. steroids
CFCs were used as refrigerants and propellants, but have largely been replaced with other
halocarbons due to the chain reaction chlorine causes with ozone.
58. Which compound(s) is often used as a solvent?
a. propanone
b. isopropyl alcohol
c. ethanol
Propanone, isopropyl alcohol, and ethanol are all used as solvents.
59. Which two classes of compounds are commonly consumed by humans?
a. esters
b. ethanol
c. ethers
Esters give flavors to many candies and fruits, and alcohol can be consumed and cause
intoxication.
60. When using hand sanitizer, you are likely using which class of organic molecules as a
disinfectant?
a. halocarbons
b. cyclic hydrocarbons
c. alcohols
d. carbonyls
Alcohols are disinfectants and solvents.
61. The toxicity of alcohols causes intoxication. Which alcohol is produced through
fermentation and consumed?
a. methanol
b. phenol
c. isopropanol
d. ethanol
Ethanol is the alcohol that is produced in fermentation and is the component of beer, wine,
and spirits that causes intoxication.
62. Natural compounds found in the human body include:
a. phenol
b. protein
c. halocarbons
d. carbohydrates
e. steroids
Natural compounds in the human body include the macromolecules and steroids.
Macromolecules include carbohydrates and proteins here, as well as fatty acids.
63. Which compound would be preferred to flavor candy?
a. methanaldehyde
b. octyl acetate
c. halocarbons
d. cyclic hydrocarbons
Esters such as octyl acetate give flavor to candy. Octyl acetate specifically has an orange
flavor.
64. Steroids found in the human body are best classified as
a. halocarbons
b. ethers
c. alcohols
d. cyclic hydrocarbons
e. esters
Steroids are considered cyclic aromatic hydrocarbons because they contain three sixmember rings fused with a five-member ring.
65. Match the function with the most likely compound:
Refrigerant --- Halocarbons
Scents and flavorings --- Methyl salicylate
Steroidal hormone --- Testosterone,
Antiseptic for surgery --- Phenol
Component of butter and cell membranes --- Fatty Acid
Fuel --- Butane
Halocarbons, Fatty Acid, Testosterone, Methyl salicylate, Phenol, Butane
Fatty acids are nonpolar and found in butter as well as in the cell membrane. Esters such
as methyl salicylate (wintergreen) are used for scents and flavoring. Alkanes such as
propane and butane are fuels for grills and stoves. Halocarbons such as CFCs and HFC are
used as refrigerants and propellents. The first antiseptic for surgery was phenol, used by
Joseph Lister. Testosterone and estrogen are two examples of steroidal hormones in the
body. [Show Less]