Question

Ethene (commonly known as ethylene) occurs in:
(a) Coal Gas
(b) Natural Gas
(c) Both of the above
(d) None of the above

Answer 1

Hint: One of the given compounds is involved in the production of ethylene, being one of its largest natural sources. Also, remember that ethylene is highly calorific in nature and a great source of fuel.

Complete step-by-step answer:
> Let us analyse ethylene as a compound to start off with.
Ethylene (IUPAC name: ethene) is a hydrocarbon which has the formula \[{{C}_{2}}{{H}_{4}}~or\text{ }{{H}_{2}}C=C{{H}_{2}}\]. It is a colourless flammable gas with a faint "sweet and musky" odour when pure. It is the simplest alkene (a hydrocarbon with carbon-carbon double bonds).
> Natural sources of ethylene include both natural gas and petroleum; it is also a naturally occurring hormone in plants, in which it inhibits growth and promotes leaf fall, and in fruits, in which it promotes ripening.
Thus, we can conclude that ethylene does occur in natural gas.
> Let us now also analyse the composition of coal gas to see if ethylene occurs in it as well.
We find that coal gas contains a variety of gases with high calorific value including hydrogen, carbon monoxide, methane, ethylene and volatile hydrocarbons together with small quantities of gases such as carbon dioxide and nitrogen.

Therefore, by this analysis, we can conclude that ethylene occurs in both natural gas and coal gas. Thus, the answer to this question is (c).

Note: Ethylene is widely used in the chemical industry, and its worldwide production exceeds that of any other organic compound. Much of this production goes toward polyethylene, a widely used plastic containing polymer chains of ethylene units in various chain lengths. Ethylene is also an important natural plant hormone and is used in agriculture to force the ripening of fruits.