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  • CHEM 109A

    • ORGANIC CHEMISTRY . CHEM 109A

    Introduction to organic chemistry. Topics include acid/base chemistry, conformational analysis, stereoisomers, thermodynamics and kinetics, aromaticity and resonance, and multistep synthesis as well as the nomenclature, structure, reactivity, and mechanisms of alkenes, alkynes, and alkyl halides. Reaction mechanisms include electrophilic addition, substitution, and elimination reactions.

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    Prerequisites: Chemistry 1C or 2C or 3C with a minimum grade of C-; or Chemistry 1B or 2B or 3B with a minimum grade of B-.

    4

    Units

    Optional

    Grading

    1, 2, 3

    Passtime

    None

    Level Limit

    Letters and science

    College
    Unlocks CHEM 6AL CHEM 6BH BIOE 243 CHEM 124 CHEM 6BL CHEM 128
    Instructors
    LEWIS R B
    Robert Lewis
    4.4
    133 reviews
    Predicted Grading Distribution
    AI predicted, based on past grading trends of the course and instructor, class info, and 127 other factors
    Lecture
    CHEM 1179
    M W F
    11:00 AM - 11:50 AM
    0 / 250
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    Enrollment Trends
    Past Enrollment Trends (16)
    See All
    Winter 2024 . Lewis R B
    CHEM 1179
    M W F
    15:00 PM - 15:50 PM
    Fall 2024 . Lewis R B
    BRDA 1610
    M W F
    13:00 PM - 13:50 PM
    Grading Trends (72)
    See All
    CHEM 109A Lewis R B Fall 2025 Total: 331
    CHEM 109A Lewis R B Winter 2025 Total: 162
    Rate My Professors
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    133
    4.4
    CHEM109ABC . Lewis R B 3 Months Ago

    Ochem is genuinely so hard that I would have changed my major if I didn't have Lewis just to avoid it. He is great at teaching and his videos are helpful if you have a hard time picking up concepts quickly in lecture like me. The other ochem professors don't have videos so keep that in mind. Ochem is hard no matter what, but he makes it better

    0 helpful 0 unhelpful
    CHEM109ABC . Lewis R B 4 Months Ago

    He's very helpful and is an awesome lecturer (especially for 109B). One of the best professors on campus tbh, reading textbook before coming to class helped even more

    0 helpful 0 unhelpful
    109A . Lewis R B 5 Months Ago

    O chem can be difficult (even as a chem major), but Lewis is seriously amazing. He's extremely clear, tests are fair, and lectures very well. I love that he's so calm, and even if I'm swamped I'll still go to lecture because he doesn't stress me out. O chem is now my favorite subject. Amazing guy. 10/10

    0 helpful 0 unhelpful
    109A . Lewis R B 6 Months Ago

    Just the best. He's clear on expectations, responds to student's discussion form questions quick, and hes pretty funny. Im in Chem 109C rn, and my only complaint is that he goes pretty fast, but I think its because he wants to give us more time to review. Definitely a difficult class!!! You gotta study on your own but Lewis is there for you.

    0 helpful 0 unhelpful
    109A . Lewis R B 6 Months Ago

    Great professor - taught from the textbook but in a way that is easier to understand. Gives you a clear pathway to succeed if you follow his advice and read the textbook before lectures and do every single possible problem.

    0 helpful 0 unhelpful
    109A . Lewis R B 7 Months Ago

    great explainer, highly reccomend for 109a, practice and textbook is key

    0 helpful 0 unhelpful
    See all 133 reviews
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    CHEM 109A
    0 / 250 Enrolled
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    M W F
    10:00 AM - 10:50 AM
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