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Professor Dave Explains
Carbon: The Element of Life
You may have heard that carbon is the element of life. What does that mean? Let's find out!
Professor Dave Explains
Will Synthetic Vitamins Make Me Explode?
The words natural and synthetic are thrown around a lot these days, when talking about foods, medicine, and other things. But what do they really mean, and how are they different? Is one necessarily better than the other? Can the...
Professor Dave Explains
Why You Should Never Say "It's Just A Theory"
A portion of our culture distrusts the scientific method, assuming that there are transcendent truths unknowable by science. But nothing is truly out of bounds for science. If it's real, it can be studied, and tested. Perhaps the...
Professor Dave Explains
Practice Problems: Labeling Carbons
What's with this hierarchy? Primary, secondary, tertiary... can't all carbons be equal? Well, no. We need to be able to label the degree of substitution of any carbon in an organic molecule so that we can make predictions about the...
Professor Dave Explains
Practice Problem: Types of Protons
We learned about how pairs of protons can have specific relationships. They can be homotopic, enantiotopic, diastereotopic, or heterotopic. Let's apply this to some examples!
Professor Dave Explains
Practice Problem: Mechanism - Reaction of an Epoxide
For this one we will have to know what epoxides do! It's a pretty neat little mechanism.
Professor Dave Explains
Practice Problem: Electrophilic Aromatic Substitution Retrosynthesis
You gotta know your EAS reactions for this one! Make sure you do them in the right order, too.
Professor Dave Explains
Practice Problem: Conversion of trans-2-butene to cis-2-butene
How can we go from one type of alkene to another? In three steps precisely? Use the reactions you know and figure it out! (Hint: Think about addition reactions, elimination reactions, and hydrogenations!)
Professor Dave Explains
Practice Problem: Reducing Agents
For this one we need to know the ability of different reducing agents to react with various functional groups.
Professor Dave Explains
No, You're Not Left-Brained or Right-Brained
Everyone has heard of the idea that some of us are "left-brained", meaning more analytical or mathematical in thinking, while some of us are "right-brained", meaning we are more creative or artistic. Here's the thing: It's rubbish! The...
Professor Dave Explains
Practice Problem: Mechanism - Acid Catalysis
For this one we need to know what happens to alcohols under acidic conditions. Beware of tricky carbocations!
Professor Dave Explains
Practice Problem: Site of Protonation on a Weak Base
For this one we will need to understand the basics about Bronsted-Lowry acid-base reactions, and we also should be able to gauge the stability of various potential conjugate bases.
Professor Dave Explains
Practice Problem: Electrophilic Aromatic Substitution Rates
We know about the products of these reactions, but how fast do they go? Give these a shot.
Professor Dave Explains
Practice Problem: E2 on Cyclic Systems and Cyclohexane Chairs
For this one we will want to recall some of the rules about doing E2 on a cyclohexane ring, as well as the relative stabilities of cyclohexane chairs. Combining concepts! Predicting kinetics!
Professor Dave Explains
Practice Problem: Analyzing Acid-Base Equilibria
Acids! Bases! Conjugate acids! Conjugate bases! We definitely have to be able to label such things, and we should also know how to state which direction in an acid-base equilibrium is preferred. To do this we should know how to tell...
Professor Dave Explains
Practice Problem: Ozonolysis Reactions
Ozone isn't just for shielding us from harmful UV radiation! It's a handy-dandy synthetic tool. Try these on for size.
Professor Dave Explains
Practice Problem: One-Dimensional Two-Body Problem
Lisa is moving again already! I dunno, I think there were bedbugs. This time you have a different plan, but you will still need kinematics and Newton's laws to find out how much time and effort stand between you and more snacks. Give it...
Professor Dave Explains
Practice Problem: Energy Diagrams
For this one we need to understand what the different parameters on an energy diagram correspond to. Check out my tutorial on this subject in the general chemistry playlist if it seems fuzzy!
Professor Dave Explains
Practice-Problem: Three-Reaction Pathway
We've got a starting material, and we are subjecting it to a series of three reaction conditions. What do we get? See if you can find out!
Professor Dave Explains
Practice Problem: Hydrogenation, Isomerism, and Cyclohexane Chairs
For this one we need to understand the stereospecificity of hydrogenation over platinum metal, stereochemical relationships, and the relative stability of cyclohexane chair conformations.
Professor Dave Explains
Practice Problem: Grignard Reactions
Grignards are all over the place! Better make sure we can draw the correct products of Grignard reactions. Try these for practice.
Professor Dave Explains
Practice Problem: Four-Reaction Pathway
We are starting with benzene, we do four reactions, and what do we get? See if you can get the right answer!
Professor Dave Explains
Practice Problem: Crossed Aldol Products
Enolate chemistry is tricky business! You might get more products than you think. Give this one a shot.
Professor Dave Explains
Practice Problem: Synthetic Strategy
We've got starting material and we've got a target molecule, and we've gotta figure out how to make the transformation in just two steps. Sift through that bag of synthetic tricks!