Investigate, write equations and construct models to represent the reactions of unsaturated hydrocarbons when added to a range of chemicals

Reaction with Hydrogen (H2)

  • Alkenes participate in an addition reaction with Hydrogen (known as hydrogenation). The double bonds between the carbon atoms break and hydrogen atoms are added in the free bonds.
  • Alkynes too give similar Hydrogenation reaction. The only difference is that since alkynes have triple bonds and only one of the bonds is broken.

Reaction with Halogens (X2)

  • When halogens react with Alkenes the C=C breaks and the halogens are added in the free bonds.
  • Alkynes also give similar reactions and the halogens replace a one bond of the triple bonds.

Reaction with Hydrogen Halides (HX)

  • Alkenes react with hydrogen halides as follows:
  • Alkynes give the following reaction:

Reaction with Water (H2O)

  • In presence of high amount of acid which has catalytic effects, Alkenes react with water to form alcohol.

Reference image for reaction:

  • Alkynes react with water in presence of acid and mercuric sulphate. The product of hydration of most alkynes are ketones.