C6.2.2 Reactions of Alkenes

• What type of hydrocarbons are alkenes?

  Unsaturated
• Alkenes are less reactive than alkanes due to their weaker pi bond.

  False
• Alkenes undergo addition reactions because of their double bond
• What type of reaction is hydrogenation of alkenes?

  Addition reaction
• Hydrogenation of ethene produces ethane.


  True
• Halogenation of ethene with bromine produces 1,2-dibromoethane
• The hydration of ethene forms ethanol.


  True
• What conditions are required for hydrogenation of alkenes?

  Catalyst, heat, pressure
• Which catalyst is used in the hydration of alkenes to form alcohols?

  Sulfuric acid
• What is the product of the reaction between ethene and bromine in halogenation?

  1,2-dibromoethane
• What is required for hydrogenation of alkenes to occur?

  Catalyst, heat, pressure
• What type of reaction is the formation of 1,2-dibromoethane from ethene and bromine?

  Addition reaction
• The product of the reaction between an alkene and a halogen is a dihaloalkane.


  True
• Hydrogenation of alkenes requires heat and pressure
• What is the defining structural feature of alkenes?

  Carbon-carbon double bond
• Alkenes can undergo addition reactions with hydrogen, halogens, and water.


  True
• What are the products of the reaction between an alkene and a halogen at room temperature?

  Dihaloalkanes
• In halogenation, the carbon-carbon double bond in the alkene breaks
• What type of alcohol is formed from the hydration of ethene?

  Ethanol
• An alkene reacts with hydrogen to form an alkane
• Alkenes contain at least one carbon-carbon double bond
• What makes alkenes highly reactive?

  Weaker pi bond
• Match the alkene property with its description:

  Unsaturated hydrocarbon ↔️ Contains a carbon-carbon double bond

  Highly reactive ↔️ Due to weaker pi bond
• Hydrogenation of alkenes requires a catalyst such as nickel
• What is formed when alkenes react with halogens in halogenation?

  Dihaloalkanes
• What type of catalyst is used in the hydration of alkenes?

  Sulfuric acid
• Alkenes are more reactive than alkanes because their pi bond is weaker
• Halogenation of alkenes requires a catalyst and high temperature.

  False
• Halogenation is an addition reaction that forms dihaloalkanes
• Halogenation of alkenes occurs at room temperature without a catalyst.


  True
• Match the reaction with its conditions:

  Hydrogenation ↔️ Catalyst, heat, pressure

  Halogenation ↔️ Room temperature, no catalyst
• The reaction of ethene with bromine occurs at room temperature without a catalyst
• What is the catalyst commonly used in the hydrogenation of alkenes?

  Nickel or platinum
• During hydrogenation, the double bond in the alkene breaks to form a single bond in the alkane.


  True
• Alkenes are highly reactive due to the weaker pi bond in their double bond.
• Match the reaction type with its conditions and products:

  Hydrogenation ↔️ Catalyst, Heat & Pressure → Alkane

  Halogenation ↔️ Room Temperature, No Catalyst → Dihaloalkane

  Hydration ↔️ Catalyst, Heat & Pressure → Alcohol
• The hydration of alkenes requires a catalyst such as sulfuric acid
• Halogenation of alkenes requires a catalyst and heat to proceed.

  False
• What is the product of the reaction between ethene and bromine?

  1,2-dibromoethane
• The hydrogenation of ethene under pressure forms ethane.


  True