chemistry study guide

Unit B: Chemistry Study Guide

1. Organic Chemistry

Functional Groups to Know:

Functional Group

Name Example

Structure or Notes

Carboxylic Acid

ethanoic acid

–COOH

Alcohol

butan-2-ol, hexan-3-ol

–OH

Ester

ethyl butanoate

–COO–

Halogenated Hydrocarbon

1,5-dichlorohexane

Contains halogens like Cl, Br, F, I

Ether (FYI only)

(e.g., in vanilla)

–O– (Not tested but appears in visuals)

Aldehyde (FYI only)

(e.g., in vanilla)

–CHO (You don’t need to memorize it)

Naming Organic Compounds:

  • Find the longest carbon chain.

  • Number to give functional group the lowest number.

  • Name substituents and functional groups.

  • Use prefixes: di-, tri- if multiple halogens or groups.

Ester Formation (Esterification):

  • Acid + Alcohol → Ester + Water

  • Catalyst: H₂SO₄ (sulfuric acid)

Example: Ethanoic acid + butan-1-ol → butyl ethanoate + H₂O

2. Acids and Bases

Properties:

Acids

Bases

Sour taste

Bitter taste

pH < 7

pH > 7

Turns blue litmus red

Turns red litmus blue

Conducts electricity (electrolyte)

Also conductive if strong

Definitions:

  • Arrhenius Acid: Produces H⁺ in solution

  • Arrhenius Base: Produces OH⁻ in solution

  • Brønsted-Lowry Acid: Proton (H⁺) donor

  • Brønsted-Lowry Base: Proton (H⁺) acceptor

3. pH and Strength of Acids/Bases

pH Scale:

  • Scale: 0–14

  • <7 = Acidic, 7 = Neutral, >7 = Basic

Strong vs Weak:

  • Strong acids/bases: Fully dissociate in water

  • Weak acids/bases: Partially dissociate

Calculating pH:

  • pH = -log[H⁺]

  • Concentration affects pH

  • Strength affects degree of dissociation, not just pH

4. Acid Deposition & the Environment

Combustion Reactions:

  • Fuel (hydrocarbon) + O₂ → CO₂ + H₂O

  • Incomplete combustion → CO or C (soot)

Oxides:

  • SO₂, NO₂ released → Combine with H₂O → acids

    • SO₂ + H₂O → H₂SO₃ (sulfurous acid)

    • SO₃ + H₂O → H₂SO₄ (sulfuric acid)

    • NO₂ + H₂O → HNO₂ and HNO₃

Impacts of Acid Rain:

  • Jet Stream: Spreads acid rain

  • Limestone Buffer: Neutralizes acid

  • Metal Leaching: Acids dissolve toxic metals into water

  • Plant nutrients: Washed away or uptake blocked

5. Reducing Environmental Impact

Solutions:

  • Scrubbers: Remove SO₂ from exhaust gases

  • Catalytic Converters: Reduce NOx emissions

  • Photochemical Smog: Controlled via alternative transportation & reducing emissions

6. Practice Concepts

Esterification Reactions to Know:

  1. ethanoic acid + butan-1-ol → butyl ethanoate + H₂O

  2. pentan-1-ol + propanoic acid → pentyl propanoate + H₂O

Functional Group ID in Structures:

  • Look for:

    • –OH = alcohol

    • –COOH = carboxylic acid

    • –Cl, –Br, –F = halogenated hydrocarbon

    • Benzene ring = aromatic compound