Download Organic Chemistry Practice Problems

Organic Chemistry
Practice Problems
Part A: Formulas of Organic Compounds
I. Empirical Formulas -­‐ Determine the empirical formula of the following compounds.
1. C2H4 2. C3H6
3. C2H6
4. C2H2
5. C2H4O2
6. CH3OH
II.
Molecular Formulas
1. A compound has the empirical formula CH2 and a molecular mass of 42.09. Deduce its molecular formula.
2. A compound has an empirical formula of CH3 and an Mr = 30. Deduce its molecular formula.
3. A compound has the empirical formula of CH2O and its Mr = 180. Calculate its molecular formula.
4. The empirical formula for vitamin C is C3H4O3. Experimental data indicates that the Mr of vitamin C is about 180. What is the molecular formula of vitamin C?
III. Structural Formulas -­‐ Draw the structural formula of the following compounds.
1. CH4
2. C3H8
3. CH3CH3
4. CH3OH
5. CH3COOH
Part B: Structural Isomerism -­‐ Draw all of the structural isomers of the following compounds.
1. C4H10
2. C5H12
3. C6H14
Part C: Organic Nomenclature
I. Name the structures from Part B.
II.
Draw the following alkenes.
1. Ethene 4. hex-­‐1-­‐ene
2. Propene 5. but-­‐2-­‐ene
3. pent-­‐2-­‐ene 6. but-­‐1-­‐ene
III. Draw or name the following alcohols.
1. methanol 2. ethanol 4. 5. 3. propan-­‐1-­‐ol 6. IV. Draw or name the following aldehydes.
1. butanal 3. 4. 3. 4. 2. propanal V.
Draw the following ketones.
1. propanone
2. butanone
VI. Draw or name the following carboxylic acids.
1. methanoic acid 2. propanoic acid Part D: Primary, Secondary and Tertiary Carbons -­‐ Identify the primary, secondary and tertiary carbons in the following compounds.
1. 2. 3. Part E: Physical Properties -­‐ Identify which compound has the greater physical property. Also, explain why.
Boiling Point Solubility
1. butane or propane 1. ethane or hexane
2. methane or methanol 2. ethanol or ethane
3. ethane or ethanoic acid 3. propane or propanone
4. butanoic acid or butanal 4. propanic acid or propan-­‐1-­‐ol
5. 2,3-­‐dimethylbutane or hexane 5. ethanoic acid or pentanoic acid
Part F: Alkane Reactions
I.Combustion -­‐ Write the balanced chemical equation for the following reactions.
Propane with excess oxygen
Pentane with excess oxygen
Butane with excess oxygen
Butane with limited oxygen (CO is produced)
Butane with extremely limited oxygen (C is produced)
II.Halogenation -­‐ Write equations showing possible steps leading to a mixture of products in the reaction between chlorine and ethane reacting together in UV light.
1. Initiation – chlorine and UV light
2. Propagation (attack the same carbon)
3. Termination – show three different possibilities
Part G: Alkene Reactions
I. Hydrogenation with H2
1. Draw the structural formulas of the reactants and products of but-­‐1-­‐ene reacting with hydrogen gas. Name the product.
2. Draw the structural formulas of the reactants and products of pent-­‐2-­‐ene reacting with hydrogen gas. Name the product.
II. Halogenation with Halogens
1. Draw the structural formulas of the reactants and products of but-­‐2-­‐ene reacting with bromine. Name the product.
2. Draw the structural formulas of the reactants and products of pent-­‐1-­‐ene reacting with bromine. Name the product.
III. Halogenation with Hydrogen Halides
1. Draw the structural formulas of the reactants and products of ethene reacting with hydrogen bromide. Name the product.
2. Draw the structural formulas of the reactants and products of hex-­‐3-­‐ene reacting with hydrogen iodide. Name the product.
IV. Hydration with Water
1. Draw the structural formulas of the reactants and products of pent-­‐1-­‐ene reacting with water (sulfuric acid and heat are added). Name the product.
2. Draw the structural formulas of the reactants and products of propene reacting with water (sulfuric acid and heat are added). Name the product.
V. Polymerization
1, Draw the structural formulas of the reactants and products when two ethene molecules react. Draw brackets around the repeating unit.
2. Draw the structural formulas of the reactants and products when two 1,2 dichloroethene molecules react. Draw brackets around the repeating unit.
Part H: Alcohol Reactions
I. Combustion -­‐ Write balanced equations for the following combustion reactions.
1. Methanol with excess oxygen
2. Ethanol with excess oxygen
II. Oxidation
a. Draw the structural formula of propan-­‐1-­‐ol. Identify the primary carbon.
b. Draw the structural formula that will form when oxidized.
c. Draw the structural formula that will form when the structure from (b.) is oxidized in re`lux.
2. a. Draw the structural formula of propan-­‐2-­‐ol. Identify the secondary carbon.
b. Draw the structural formula that will form when (a.) is oxidized.
Part I: Halogenoalkanes with -­‐OH
Primary Halagenoalkanes
a. Draw the structural formula of chloromethane. Identify the primary carbon.
b. Draw an OH-­‐ nucleophile attacking. Include curly arrows to represent the movement of electron pairs.
c. Draw the structural formula of the unstable transition state when an OH-­‐ nucleophile attacks.
d. Draw the structural formula of the products after the unstable transition state breaks apart. Name the compounds generated.
Tertiary Halagenoalkanes
a. Draw the structural formula of 2-­‐chloro 2-­‐methyl propane. Identify the tertiary carbon.
b. Draw the carbocation intermediate that will form when the OH-­‐ is added. Include curly arrows to represent the movement of electron pairs.
c. Draw the structural formula of the product after the OH-­‐ attacks. Name the compound generated.