Why are alkenes and alkynes regarded as unsaturated hydrocarbons? Discuss the structures of ethene and ethyne.

Discuss the structure of ethene.

Alkynes are unsaturated hydrocarbons. Justify this statement giving two reasons.

Ethyne (C_2H_2) is unsaturated hydrocarbon. Explain.

An alkyne with five carbon atoms per molecule when passed through dilute sulphuric acid containing mercuric sulphate gives a compound which forms an oxime but has no effect on Fehling's solution. The compound on oxidation gives dimethyl acetic acid. It reacts with sodamide to form a hydrocarbon. What is the structure of the alkyne ?

Why are certain compounds called hydrocarbons? Write the general formula for homologous series of alkenes and alkynes and also draw the structure of the first member of each series. Write the name of the reaction that converts alkenes into alkanes and also write a chemical equation to show the necessary conditions for the reaction to occur.

Choose the most appropriate answer for each of the following: Identify the statement which does not describe the property of alkenes : (A) They are unsaturated hydrocarbons (B) They decolourise bromine water (C) They can undergo addition as well as substitution reactions (D) They undergo combustion with oxygen forming carbon dioxide and water.

Distinguish between the saturated hydrocarbon ethane and the unsaturated hydrocarbon ethene by drawing their structural formulae.

Distinguish between the saturated hydrocarbon ethane and the unsaturated hydrocarbon ethene by drawing their structural formulae.

(a) Give a chemical test to distinguish between saturated and unsaturated hydrocarbon. (b) Name the products formed when ethane burns in air. Write the balanced chemical equatioin for the reaction showing the types of energies liberated. (c) Why is reactiion between methane and chlorine in the presence of sunlight considered a substitution reaction ?

a. Give the structure of lowest molecular mass and optically active alkyne. b. Give the structure of unsaturated hydrocarbon with lowest molecular mass showing diastereomers. c. Give the structure of alkyne that gives the same product on reaction with either H_2+Ni_2B or K+C_2H_5OH . d. Give the structure of alkyne that gives the same single product on reaction with either (B_2H_6//THF+H_2O_2//overset(Ө)H) or dil. H_2SO_4//Hg^(2+)//H^(o+) . e. Give the structure of alkyne that gives the same two products with either of the reagents in (d).