Answer. Organic compounds containing double bond in their molecules are called alkenes, such as:
H2C = CH2
Ethene
Organic compounds containing triple bond in their molecules are called alkynes, such as:
HC ≡ CH
Ethene (Acetylene)
Identification from other compounds
(i) Bromine water test:
Dissolve a pinch of the given organic compound in 2.0cm3 of carbon tetrachloride (CCI4). Add 2-cm3 of bromine water in it. Bromine will be decolorized which confirms the presence of double or triple bond.
(ii) Baeyer's test:
Dissolve about 0.2 g of the organic compound in water. Add 2-3 drops of alkaline KMnO4 solution in the aqueous solution of organic compound. Pink colour will disappear. This confirms the presence of double or triple bond.