Substitution and Elimination reactions are potentially the most difficult concepts covered at the Organic Chemistry 1 level. In addition to studying the SN1 SN2 E1 and E2 reaction mechanisms, you also have to understand the similarities and differences so that you can derive the correct products for specific reaction conditions.
I’ve put together this medium/tricky quiz to help you practice the reactions and gauge your level of comprehension.
Not fully confident yet? Go back and review my entire SN1 SN2 E1 E2 reaction video series and study the associated cheat sheet before getting started. So take your time as you go through the questions. If you get stuck just visit the video series page (linked above) and watch the related tutorial.
Download PDF Solutions posted at the end of the quiz.
Substitution Elimination Practice Problems
Question 1: Rank the following nucleophiles in order of increasing strength
Need help? Watch the Nucleophile vs Base videos in the series
Question 2: Arrange the following molecules in order of increasing reactivity/ability for a unimolecular elimination reaction. (E1)
Question 3: Arrange the following molecules in order of increasing reactivity to undergo a bimolecular substitution reaction (SN2)
Question 4: Which direction is favored at equilibrium when dissolved in an acetone solution? What about methanol?
Need help? see the solvents video in the series
Predict the product for each of the following reactions. Be sure to show stereochemistry when appropriate. Be sure to label major/minor products when more than one outcome is possible.
Question 5:
Question 6
Question 7
Question 8
Question 9
Question 10
Question 11
Question 12
Question 13
Question 14
Question 15
Question 16
Question 17
Question 18 Draw ALL possible starting haloalkanes that would form this product when undergoing unimolecular elimination.
Question 19: Show how to bring about the following transformation. You may use any reactants and reagents necessary
Question 20: Predict the product/s when (2R,3S) 3-ethyl-2-iodohexane reacts with NaSCH3 in dimethyl sulfoxide.
Question 21: Draw a complete mechanism for the following reaction. Be sure to include all intermediates, formal charges, and pushing arrows.
Bonus Question 22: Show how to bring about the following transformation. Hint: Pay attention to the orientation of substituents
Bonus Question 23: Show the complete mechanism for the following transformation. Hint: More than one reaction is required.
What did you think of this quiz? Easy? Hard? Need more practice?
Send Me The solutions >>
hello ! I can’t get the answers via email. Thank you in advance !
Hi Frida, if the solutions don’t come to the email you entered, try looking in the spam folder or maybe try entering in a different email.
Thank you so much mam
You’re welcome, Monish!
I m unable to get solutions..i filled the details but didnt receive the mail
Try signing up again
Ms. Leah, can you please explain number 1? Why is NaSCH3 stronger than NaOCH3? I watched your video again and again, but isn’t the answer different from protic to aprotic? If it is protic, Sulfur should be stronger than O but if aprotic, O is stronger than S? I am so confused…….does that question have to specify that or polar protic is given? Or am I not understanding something? And why is Carboxylic acid weaker than CH3OH?
I’m so lost… please help.
I don’t understand why you’re asking about solvent here Hoeun. S is a stronger nucleophile compared to O due to its larger size
could i get the answer to these the email didn’t come
Email me Natalie
can someone explain me question 13?
Did you check the solutions Yossi?
question 15 is quit tricky for me. I haven’t received the solutions yet so can anyone tell me how to go about it? How do you solve for the OH
Jay: Email me if you still haven’t received the solutions
I’m not having the answers,can’t wait to see them….
If you signed up you should have received them within 5 minutes Enida
On question 1, how does NaSCH3 differ from CH3S? NaSCH3 should disassociate to Na+ and -SCH3. How come CH3S isn’t negatively charged?
Steven, Error on my part. thanks for pointing it out
Good Leah you are beautiful
why is question 20 not an E2 reaction?
negative sulfur makes a strong nucleophile but weak base. This means it prefers SN2 over E2. In addition, since the reaction takes place in a polar aprotic solvent, SN2 is favored once more over E2
i can’t open the quiz solutions easily, i can’t open the link. idk if i need to pay something or?
It’s free. Did you get the email?
i do not understand why question Number 5 is an Sn2. the Nucleophile is strong but the solvent is polar and protic, which means Sn2 cannot happen, CH3O^- is a strong base so it will do E2, especially that the substrate is primary
It is not possible to form a pi bond on a primary benzyl carbon since the benzene ring is already maxed out with bonds and does not have a free hydrogen atom. This is a trick question because even though E2 would be most favorable the reaction proceeds SN2 as the less-likely but only possible option
This quiz was about medium difficulty. I took it once and didn’t understand it. I studied for many hours and now I find it to be a medium difficulty.
That’s awesome Michell. There are a few mistakes which I plan to correct shortly
These are really helpful and sums up all we learned in the boot camp
Thanks Leah!!!!
Thanks Danielle! Glad you found it helpful
Thank you so much Leah
Thank you Ahmed. did you find it easy or difficult?