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Elimination reactions
In this type of reaction a small molecule is lost from a larger one, usually resulting in the formation of a double bond. The most commonly eliminated molecules are HBr, HCl and H2O.
It generally helps, when working out these reactions, to draw out the displayed formula of the starting molecule. You will be removing a Br, Cl or OH atom/group and a hydrogen atom from an adjacent carbon atom. If you draw a box around the eliminated molecule, cross it out, and replace it with your double bond, you should end up with the correct molecule, correctly bonded:
We saw in the alcohols topic the elimination of water from an alcohol to give an alkene:
Animation - dehydration of propan-1-ol
