Reactions of Alkenes
Alkenes Worksheet
1. Hydrogenation of Propene
Propene can react with hydrogen in the presence of an appropriate catalyst.
a. Write a symbol equation for the reaction that takes place.
Equation:
CH3CH=CH2 + H2 → CH3CH2CH3
b. Suggest a suitable catalyst for the reaction.
Nickel
2. Halogenation of But-1-ene
But-1-ene will react with chlorine in the absence of UV light.
a. Draw the skeletal formula of the product from this reaction.
Answer:
b. State the mechanism of this reaction.
Electrophilic Addition
c. Write a symbol equation for the reaction that takes place.
Equation:
CH3CH2CH=CH2 + Cl2 → CH3CH2CHClCH2Cl
3. Hydration of Ethene
Ethanol can be produced from the reaction between ethene and steam in the presence of a catalyst.
a. Suggest a substance for a suitable catalyst. State the conditions used in the reaction.
Catalyst & Conditions:
- Catalyst: Concentrated Phosphoric acid (H3PO4) or Sulfuric acid.
- Temperature: 300°C
- Pressure: 60 atm (6000 kPa)
b. Write an equation for this reaction.
Equation:
CH2=CH2 + H2O → CH3CH2OH
4. Reaction with Hydrogen Bromide
Propene can react with hydrogen bromide in an addition reaction.
a. Draw the two possible products of this reaction.
Answer:
(Major product: 2-bromopropane, Minor product: 1-bromopropane)
b. Write an equation for the reaction. You do not have to show the structure of the product.
Equation:
C3H6 + HBr → C3H7Br
5. Reaction with Sulfuric Acid
But-1-ene reacts with sulfuric acid to produce two possible products.
a. State the name of the organic product that is formed in this reaction, and draw their structures.
Answer:
b. A scientist wants to ensure that they only form one of the two isomers. What alternative reactant could they use to achieve this?
Use But-2-ene
But-2-ene is a symmetrical alkene. Reaction with sulfuric acid will yield only one product (2-butyl hydrogen sulfate) because addition to either carbon of the double bond results in the same structure.