Organic Chemistry and the MCAT, by Leah Fisch

Leah Fisch Notation from James: This is a guest mail service by Leah Fisch of Leah4Sci.com , an online resource for learning organic chemical science, MCAT preparation, and other science topics . This is a comprehensive Leah wrote on organic chemistry and the MCAT. You might want to bookmark this page for future reference, and be sure to visit Leah's Youtube Channel for more videos on nomenclature as well as other organic chemistry topics. Leah also tutors MCAT and organic chemical science. Her tutoring page is here.

Finally: If you're planning on taking the MCAT soon, you lot should download Leah's free 6-Weeks To MCAT Prep Guide.

Exactly how much organic chemical science is on the MCAT?

As a premed student, organic chemistry is likely one of the virtually difficult sciences y'all've encountered. Why have such a difficult class? Because you need it for the MCAT!

Still, in 2015, when the MCAT test inverse, the amount of organic chemistry appeared to decrease, making students wonder only how much time they should dedicate to the topic.

Implication: "is it even worth it?"

The answer is catchy. And then instead of telling you how much to study… let's interruption it down.

The MCAT has a total of 4 sections covering 8 disciplines:

  • Physics
  • General Chemistry
  • Organic Chemistry
  • Biochemistry
  • Biology
  • Psychology
  • Sociology
  • Verbal Reasoning (CARS)

Organic chemical science is just Ane of the eight subjects y'all accept to report.

But information technology gets better:  orgo shows upwardly in just the outset and 3rd section of the 7.5 hour examination.

Section 1: Chemical and Physical Foundations of Biological Systems is just 15% organic chemistry with the other 85% comprised of general chemistry, biochemistry, physics and biological science.

Section 3: Biological and Biochemical Foundations of Living Systems is just 5% organic chemistry with the other 95% comprised of general chemistry, biochemistry and biological science.

After a quick calculation organic chemistry appears to exist merely 5% of the entire exam!

But… don't let the 5% gauge requite yous a false sense of security.

Biology is the near highly tested topic, but when yous run the math it makes up but xviii.75% of the MCAT.

Sounds depression?

The math is somewhat misleading.

Beginning of all, when medical schools evaluate your application, they await at more just your full score. They look to see how you scored in each section, making organic chemistry of a sudden more valuable. Consequently, even though it's a pocket-size part of just two sections on the MCAT, skipping orgo study will tank your score in these sections, making you look bad.

The virtually important thing to recognize is simply HOW organic chemistry is tested.

15 percent of the beginning section doesn't mean that 8.85 of 59 questions volition be isolated organic chemistry questions.

Instead, the new MCAT is an integrated exam where y'all'll be faced with enquiry- and experiment-style passages combining multiple disciplines into a single passage and question:

  • While you may not be asked for an R/South question direct, you may exist asked nigh the optical purity of a newly synthesized experimental drug.
  • Y'all may non exist tested on aldol condensations directly, but you may face a question asking y'all how glycolysis will be impacted by a unmarried amino acrid mutation in the active site of aldolase, which is the enzyme that catalyzes an aldol-fashion reaction in glycolysis.

Understanding Concepts is MUCH More than Important than Memorization!

Your orgo professor likely asked FOR reactions, mechanisms, products, and lots of pushing arrows.

The MCAT is all multiple pick questions and applied concepts.

As you review reactions, don't worry well-nigh memorizing mechanisms.

Instead, make sure to ask yourself these questions every step of the style.

  • What is the purpose of this reaction?
  • What is the purpose of this mechanism?
  • What exercise I admittedly have to recognize about the reactant and reagent to assistance me sympathize the product? Focus on getting the logic, understanding the patterns and agreement what's going on.

For case, Grignards are VERY reactive. They'll assault all sorts of carbonyls. Don't worry nigh which specific pair of electrons attack. Instead brand sure you recognize the resulting alcohol product.

Why can't you dissolve a Grignard in water or ethanol? Why should you consummate the reaction with an acrid workup AFTER the Grignard reacted? What happens if you mix the aqueous acid with the Grignard at the start of the reaction?

And most chiefly, can yous recognize the specific functional groups of this reaction when presented in the context of a biological or chemical enquiry experiment?

As an MCAT tutor I've been interviewing students subsequently each exam to understand the true nature of questions that ascend on the test.

This is where it gets interesting.

Once more, looking at only xv% orgo on the first section I notice an AVERAGE of 15% orgo questions. That is an average over the course of many exams combined.

One test may accept just ii to three orgo questions about functional groups, Due southN1 reactions or IR spec, while another exam will accept as many as 15 organic chemistry questions.

Another thing I've noticed is that while y'all may have learned a certain topic in your organic chemical science course, the MCAT will find a manner to examination it nether the disguise of biological science or biochemistry. This is peculiarly true with amino acid characteristics, separation techniques and of class chirality.

This makes the value of your organic chemistry study much more significant, as orgo success volition be success in the other subjects too.

What does this mean for you equally a premed student?

"What about high yield topics?"

Students looking for shortcuts ofttimes want to know which high-yield orgo topics to study.

In other words: "if I only have fourth dimension to cover a chip of orgo, which topics should I focus on?"

This is a trick question.

I've heard from MCAT testers that any given MCAT has covered multiple passages on a single "low-yield" topic. Students who've studied everything will get these correct. Students who followed their MCAT book's communication on loftier-yield topics ONLY wound up missing out on quite a few elementary (low yield) questions.

For example, ane of the 2016 MCATs had no less than Five passages related to lab separation techniques. If you thought, "sure I'll cover electrophoresis quickly" and didn't written report it well enough, you would have missed out on several questions.

With all of this in mind, brand certain y'all absolutely main the following starting with all of the beginner orgo topics typically covered in first semester organic chemistry. And so focus on understanding the patterns and functional groups of reactions covered in orgo ii.

Why? Considering organic chemistry two is simply orgo 1 on steroids building on these very foundations.

Here's my recommendation for what to comprehend when studying organic chemistry for the MCAT

The following is non an exhaustive listing but a very adept start on what to focus on:

1. Commencement With The Nuts

The AAMC considers some of these "general chemistry" topics but yous likely covered this in organic chemistry 1.

  • Lewis structure and bonding
  • Hybridization, bail angles and electronic/molecular geometry [video]
  • Structural formulas including skeletal structure (bond line notation) [video]

Nomenclature

Let's face it, while you lot won't be tested the classification itself, you better know exactly what is meant by isopropyl, tert-butyl and more than.

2. Isomers and Stereochemistry

  • structural isomers (ramble isomers) [video]
  • conformational isomers including Newman and Chair
  • Chirality including R/Southward, D/L, enantiomers, diastereomers, meso compounds and more
  • cis/trans and E/Z
  • Acids & Bases: The not-math (non gen chem) aspect (such as acidity trends)
  • SN1/SN2/E1/E2 Reactions and how to differentiate between them

3. The post-obit topics are sometimes covered in Org 1 or Org 2. Learn these well just don't become too crazy!

  • Alcohols & Phenols: Reactions, protecting groups, leaving groups
  • Aromaticity: Concept more than reactions including heterocyclic effluvious compounds
  • Aldehyde and Ketone: Direct Reactions, Reactions at the Alpha Carbon (enolates), Keto-Enol Tautomerism (KET) and more
  • Amine reactions peculiarly equally they chronicle to amino acids
  • Carboxylic Acids: Germination and Reactions
  • Carboxylic Acid Derivatives, especially esters in biological molecules

4. The following topics are often introduced in orgo simply covered in biochemistry

  • Carbohydrates: orgo focus on Fischer Projections, stereochemistry and some reactions
  • Amino Acids: orgo focus on Fischer Projections, stereochemistry and some reactions

v. And permit's not forget Lab Techniques

If the MCAT is all about experiments and research, make sure you know and truly sympathise the post-obit analytical methods including simple graph estimation:

  • thirteenC and 1H-NMR [video]
  • IR (Infrared spectroscopy)
  • UV (Ultraviolet spectroscopy)

Separation Techniques

  • Extraction
  • Distillation
  • Chromatography

6. What about all those crazy orgo 2 reactions not listed above?

Don't skip them completely just in case .

Don't go basics as you review but only expect at your book and try to sympathize what's going on.

For example Acetoacetic Ester Synthesis, Michael Add-on and more. These are SPECIFIC reactions that incorporate $.25 and pieces of the reactions listed to a higher place.

And then while you're not required to know this machinery, acetoacetic ester synthesis is actually just a combination of the following reactions:

  • Acid base
  • SNii
  • aridity/elimination
  • Keto Enol Tautomerization

I challenge you to go written report the steps and verify that the above is true.

The MCAT EXPECTS you to recognize that this is the case, simply in reality most students are nether as well much force per unit area to make these connections.

To be prophylactic, spend some time each day watching a short avant-garde reaction mechanism tutorial video or reviewing a single reaction in your orgo book. Let the volume/tutorial brand the connections for you and so that your brain power is reserved for figuring out what the heck they are asking in the passage/question.

Allow's accept this to the farthermost.

Nowhere on the AAMC outline practice yous see the mention of alkenes.

Does this mean you can skip it? Non quite!

Let'south read between the lines:

  • E1/E2 including booze dehydration = alkenes.
  • What if you reverse the reaction?That'due south an alkene addition reaction!
  • What if you have to synthesize an alcohol?Alkenes make good starting points.
  • What almost Cis/Trans East/Z isomers equally the product of a reaction?

Once once more, alkene reactions.

And yes, MCAT testers HAVE confirmed seeing all of this on their MCAT.

What does this hateful for you lot as a premed student?

Practice Non discount organic chemistry just because there's so much else to study.

Instead I recommend breaking upwardly your study schedule so that you devote time to cover a little scrap of EACH MCAT topic on a weekly basis including organic chemistry.

And then how do you structure your schedule in a manner that allows you to cover ALL of the content for the MCAT and work in practice questions and full lengths, without forgetting or burning out?

Download my free 'six Weeks to MCAT Prep Guide' by visiting Leah4sci.com

Thanks for demystifying the contempo changes to the MCAT Leah – and best wishes to everyone for a successful test! – J