Call Now to Set Up Tutoring:

(888) 888-0446

AP Chemistry : Oxidation-Reduction Reactions

Study concepts, example questions & explanations for AP Chemistry

Create An Account

All AP Chemistry Resources

6 Diagnostic Tests 225 Practice Tests Question of the Day Flashcards Learn by Concept

Example Questions

← Previous 1 2 3 4 Next →

Example Question #1 : Oxidation Reduction Reactions

What is the balanced equation when heptane is combusted?

Possible Answers:

2 C₇H₁₄ + 5 O₂ → 3 H₂O + 6 CO₂

C₇H₁₆ + O₂ → H₂O + CO₂

C₃H₈ + 5 O₂ → 4 H₂O + 3 CO₂

C₅H₁₂ + 8 O₂ → 6 H₂O + 5 CO₂

C₇H₁₆ + 11 O₂ → 8 H₂O + 7 CO₂

Correct answer:

C₇H₁₆ + 11 O₂ → 8 H₂O + 7 CO₂

Explanation:

Heptane: C₇H₁₆. Combustion is when a molecule reacts with O₂ and the products are CO₂ and H₂O. Balancing gives 7 CO₂, 8 H₂O, 1 heptane, and 11 O₂

Report an Error

Example Question #1 : Reaction Types

Which of the following reactions has the most exothermic heat of reaction?

Possible Answers:

The combustion of propane

The combustion of butane

The combustion of methane

The combustion of isopropane

The combustion of isobutane

Correct answer: The combustion of butane

Explanation:

The longer the hydrocarbon chain, the greater the amount of combustion products (CO2 and H20) generated. Branched molecules such as isopropane and isobutane are more difficult to combust than their straight-chain counterparts.

Report an Error

Example Question #3 : Oxidation Reduction Reactions

Which of the following conditions would describe a combustion reaction?

Possible Answers:

Exothermic with a positive $\Delta H$

Endothermic with a positive $\Delta H$

Endergonic with a negative $\Delta H$

Exothermic with a negative $\Delta H$

Exergonic with a positive $\Delta H$

Correct answer:

Exothermic with a negative $\Delta H$

Explanation:

An exothermic reaction will have a negative $\Delta H$ value, indicating that it releases heat. Conversely, an endothermic reaction will have a positive $\Delta H$ value, indicating a consumption of heat.

A combustion reaction releases heat; thus it must have a negative $\Delta H$ value and be exothermic.

Exergonic reactions have a negative $\Delta G$ value, indicating spontaneity, while endergonic reactions are non-spontaneous. While most combustion reactions will be non-spontaneous, it is impossible to draw this conclusion for certain without knowing more about the reaction. The only thing we know for certain is that heat is released, and the reaction is exothermic.

Report an Error

Example Question #51 : Reaction Types

The following ReDox reaction takes place in acidic solution:

Fe²⁺ + Cr₂O₇^2– → Fe³⁺ + Cr³⁺

What is the sum of coefficients in this redox reaction?

Possible Answers:

Correct answer:

Explanation:

When you balance the redox reaction in acidic conditons, there are 6Fe²⁺, 1 Cr₂O₇^2–, 14 H⁺, 6 Fe³⁺, 2 Cr³⁺, and 7 H₂O. Don't forget to add the 1 in front of the Cr₂O₇^2–

Report an Error

Example Question #2 : Balancing Oxidation Reduction Reactions

For the following unbalanced redox reaction, how many electrons are transferred and which chemical species is being oxidized?

$PF_2I_{(l)}+Hg_{(l)}\rightarrow P_2F_4_{(g)}+Hg_2I_2_{(s)}$

Possible Answers:

Two electrons are transferred; Hg is oxidized

One electron is transferred; Hg is oxidized

Two electrons are transferred; P is oxidized

One electron is transferred; P is oxidized

Correct answer:

Two electrons are transferred; Hg is oxidized

Explanation:

To begin, we will need to separate the given reaction into the two half-reactions by identifying changes in oxidation number. In this case, mercury (Hg) and phosphorus (P) show a change in oxidation number. Mercury begins with an oxidation number of zero, and ends with an oxidation number of . Phosphorus begins with an oxidation number of and ends with an oxidation number of . Note that the oxidation numbers for fluorine and iodine reamain constant at for each.

Now we can begin to look at the half-reactions.

$PF_2I_{(l)}\rightarrow P_2F_4_{(g)}$

$Hg_{(l)}\rightarrow Hg_2I_2_{(s)}$

Balance the atoms.

$2PF_2I_{(l)}\rightarrow P_2F_4_{(g)}$

$2Hg_{(l)}\rightarrow Hg_2I_2_{(s)}$

Now balance the electrons. We know that each mercury atom loses one electron and each fluorine atom gains one electron.

$2PF_2I_{(l)}+2e^-\rightarrow P_2F_4_{(g)}$

$2Hg \rightarrow Hg_2I_2_{(s)}+2e^{-}$

We can see that two electrons are tranferred. To identify the element being oxidized, we must find the element that is losing electrons. In this case, mercury is being oxidized.

Report an Error

Example Question #1 : Oxidation Reduction Reactions

How many electrons are involved in the following reaction?

$MnO_4^-+ Fe^{2+} \rightarrow Fe^{3+}+Mn^{2+}$

Possible Answers:

1 e^-

5 e^-

3 e^-

4 e^-

2 e^-

Correct answer:

5 e^-

Explanation:

The common factor between 1 e^- and 5 e^- is 5. Therefore the number of electrons involved is 5 e^-.

Report an Error

Example Question #4 : Balancing Oxidation Reduction Reactions

How many electrons are involved in the following reaction?

$MnO_4^-+ I^-\rightarrow I_2+Mn^{2+}$

Possible Answers:

5 e^-

1 e^-

2 e^-

4 e^-

10 e^-

Correct answer:

10 e^-

Explanation:

The common factor between 2 e^- and 5 e^- is 10. Therefore the number of electrons involved is 10 e^-.

Report an Error

Example Question #5 : Balancing Oxidation Reduction Reactions

What is the balanced coefficient on OH^- for the following reaction:

$Br^- + MnO_4^- \rightarrow MnO_2 + BrO_3^-$ (under basic conditions)

Possible Answers:

Correct answer:

Explanation:

Add them together:

$3 H_2 O + Br^- + 2 MnO_4^- + 8 H^+ + 6 e^- \rightarrow 2 MnO_2 + BrO_3^- + 6 H^+ + 4 H_2 O + 6 e^-$

Simplify:

$Br^- + 2 MnO_4^- + 2 H^+ \rightarrow 2 MnO_2 + BrO_3^- + H_2 O$

Add Hydroxides to each side to counter H⁺_.

$Br^- + 2 MnO_4^- + 2 H_2 O \rightarrow 2 MnO_2 + BrO_3^- + H_2 O+2 OH^-$

Simplify:

$Br^- + 2 MnO_4^- + H_2 O \rightarrow 2 MnO_2 + BrO_3^- +2 OH^-$

Report an Error

Example Question #6 : Balancing Oxidation Reduction Reactions

What is the sum of all the balanced coefficients in the following reaction:

$O_2 + Sb \rightarrow H_2 O_2 + SbO_2^-$ (basic conditions)

Possible Answers:

Correct answer:

Explanation:

Add the equations together

$2Sb+4H_2 O + 3 O_2 + 6 H^+ + 6e^- \rightarrow 2SbO_2^-+8H^++3 H_2 O_2 + 6e^-$

Simplify

$2Sb+4H_2 O+3 O_2 \rightarrow 2SbO_2^-+2H^++3H_2 O_2$

Add 2 OH^- to each side to cancel out the H⁺_.

$2Sb+4H_2 O+3 O_2 + 2 OH^- \rightarrow 2SbO_2^-+2H_2 O+3H_2 O_2$

Simplify:

$2Sb+2 H_2 O+3 O_2 + 2 OH^- \rightarrow 2SbO_2^-+3H_2 O_2$

Report an Error

Example Question #4 : Oxidation Reduction Reactions

$Fe_{(s)} + 2HCl_{(aq)} \rightarrow FeCl_{2(aq)} + H_{2(g)}$

For the redox reaction shown, which of the following half reactions occurs in the anode?

Possible Answers:

$Fe \rightarrow Fe^{3+} + 3e^{-}$

$Fe^{2+} + 2e^{-} \rightarrow Fe$

$Fe \rightarrow Fe^{2+} + 2e^{-}$

$2H_{2} + 2e^{-} \rightarrow H_{2}$

Correct answer:

$Fe \rightarrow Fe^{2+} + 2e^{-}$

Explanation:

Recall that oxidation always occurs at the anode (in both the electrochemical and galvanic cells). loses two electrons in this case to become $Fe^{2+}$ . The presence of $Fe^{2+}$ is hinted by the ionic compound FeCl_2 _.

Report an Error

← Previous 1 2 3 4 Next →

View AP Chemistry Tutors

Matthew
Certified Tutor

Rider University, Bachelor of Science, Chemistry. Rutgers University-Camden, Master of Science, Organic Chemistry.

View AP Chemistry Tutors

Justin
Certified Tutor

University of Washington-Seattle Campus, Current Undergrad Student, Biomedical Engineering.

View AP Chemistry Tutors

Oselen
Certified Tutor

UNIVERSITY OF BENIN, Bachelor of Science, Mechanical Engineering. University of Windsor, Master of Science, Mechanical Engine...

All AP Chemistry Resources

6 Diagnostic Tests 225 Practice Tests Question of the Day Flashcards Learn by Concept

Popular Subjects

Math Tutors in Los Angeles, Calculus Tutors in Philadelphia, Chemistry Tutors in Atlanta, LSAT Tutors in Seattle, Biology Tutors in Seattle, LSAT Tutors in Houston, French Tutors in Los Angeles, ACT Tutors in Houston, MCAT Tutors in Washington DC, French Tutors in Denver

Popular Courses & Classes

ACT Courses & Classes in San Diego, SAT Courses & Classes in Phoenix, Spanish Courses & Classes in Dallas Fort Worth, LSAT Courses & Classes in Los Angeles, GRE Courses & Classes in Atlanta, MCAT Courses & Classes in New York City, GRE Courses & Classes in Philadelphia, GMAT Courses & Classes in Chicago, ISEE Courses & Classes in San Francisco-Bay Area, GMAT Courses & Classes in Houston

Popular Test Prep

ACT Test Prep in Miami, ISEE Test Prep in Boston, SAT Test Prep in Miami, SAT Test Prep in Washington DC, GMAT Test Prep in Houston, ACT Test Prep in Los Angeles, ISEE Test Prep in New York City, ACT Test Prep in Dallas Fort Worth, ACT Test Prep in San Diego, GRE Test Prep in Phoenix

DMCA Complaint

If you believe that content available by means of the Website (as defined in our Terms of Service) infringes one or more of your copyrights, please notify us by providing a written notice (“Infringement Notice”) containing the information described below to the designated agent listed below. If Varsity Tutors takes action in response to an Infringement Notice, it will make a good faith attempt to contact the party that made such content available by means of the most recent email address, if any, provided by such party to Varsity Tutors.

Your Infringement Notice may be forwarded to the party that made the content available or to third parties such as ChillingEffects.org.

Please be advised that you will be liable for damages (including costs and attorneys’ fees) if you materially misrepresent that a product or activity is infringing your copyrights. Thus, if you are not sure content located on or linked-to by the Website infringes your copyright, you should consider first contacting an attorney.

Please follow these steps to file a notice:

You must include the following:

A physical or electronic signature of the copyright owner or a person authorized to act on their behalf; An identification of the copyright claimed to have been infringed; A description of the nature and exact location of the content that you claim to infringe your copyright, in \ sufficient detail to permit Varsity Tutors to find and positively identify that content; for example we require a link to the specific question (not just the name of the question) that contains the content and a description of which specific portion of the question – an image, a link, the text, etc – your complaint refers to; Your name, address, telephone number and email address; and A statement by you: (a) that you believe in good faith that the use of the content that you claim to infringe your copyright is not authorized by law, or by the copyright owner or such owner’s agent; (b) that all of the information contained in your Infringement Notice is accurate, and (c) under penalty of perjury, that you are either the copyright owner or a person authorized to act on their behalf.

Send your complaint to our designated agent at:

Charles Cohn Varsity Tutors LLC
101 S. Hanley Rd, Suite 300
St. Louis, MO 63105

Or fill out the form below:

Do not fill in this field

Contact Information

* Full legal name

Company name

* Phone number

* Email address

Address

* Address1

Address2

* City

* State

* Zipcode

* Country

Complaint Details

* URL of copyrighted work (where your original material is located)

* Please describe the copyrighted work so that it may be easily identified

I am the owner, or an agent authorized to act on behalf of the owner of an exclusive right that is allegedly infringed.

I have a good faith belief that the use of the material in the manner complained of is not authorized by the copyright owner, its agent, or the law.

This notification is accurate.

I acknowledge that there may be adverse legal consequences for making false or bad faith allegations of copyright infringement by using this process.

* Signature (your digital signature is legally binding)

HIGH SCHOOL

GRADUATE SCHOOL

K-8

Search 50+ Tests

math tutoring

science tutoring

foreign languages

elementary tutoring

other

Search 350+ Subjects

AP Chemistry : Oxidation-Reduction Reactions

Study concepts, example questions & explanations for AP Chemistry

All AP Chemistry Resources

Example Questions

Example Question #1 : Oxidation Reduction Reactions

Example Question #1 : Reaction Types

Example Question #3 : Oxidation Reduction Reactions

Example Question #51 : Reaction Types

Example Question #2 : Balancing Oxidation Reduction Reactions

Example Question #1 : Oxidation Reduction Reactions

Example Question #4 : Balancing Oxidation Reduction Reactions

Example Question #5 : Balancing Oxidation Reduction Reactions

Example Question #6 : Balancing Oxidation Reduction Reactions

Example Question #4 : Oxidation Reduction Reactions

All AP Chemistry Resources

Report an issue with this question

DMCA Complaint

Contact Information

Address

Complaint Details

Email address:
Your name:
Feedback: