Question

For artificial ripening of fruit, ____ gas is used:
A. methane
B. acetylene
C. butane
D. helium

Answer 1

For this problem, we have to study the plant hormones and the gas which affects them. Then we will be able to recognise the correct gas which is used for the artificial ripening of fruit. This particular gas is also used for welding purposes in combination with oxygen.

Complete step by step solution:
-In the given question, we have to identify the correct gas which is responsible for the artificial ripening of the fruit.
-The hormones responsible for the growth and development of the plant is known as plant growth.
-There are many types of plant growth hormones such as gibberellins, cytokinin, ethylene and abscisic acid.
-Among all the hormones, ethylene is responsible for the faster ripening of the fruit because it helps in increasing the rate of respiration, change in colour, odour and taste.
-Here, ethylene is produced naturally by the plants but for the artificial ripening of fruit, we use acetylene gas.
-For the production of acetylene gas, calcium carbide is used. When it comes in contact with the moisture it yields calcium hydroxide as well as acetylene gas which works similar to the ethylene.
-The balanced chemical reaction is:
$\text{Ca}{{\text{C}}_{2}}\text{ + }{{\text{H}}_{2}}\text{O }\to \text{ }{{\text{C}}_{2}}{{\text{H}}_{2}}\text{ + Ca(OH}{{\text{)}}_{2}}$
-That's why ethylene gas and acetylene gas are considered as ripening agents.

Therefore, option (B) is the correct answer.

Note: The process of ripening of the fruit can be determined with the help of iodine. Because if the ripening of the fruit has not started then the colour of iodine will immediately turn black. If the colour of the iodine solution remains yellow or orange it means that the fruit is slightly rotten.