[B] It reacts with moisture and releases Acetaldehyde, which in turn releases ethylene
[C] It reacts with starch and releases Acetylene
[D] It reacts with moisture and releases Ethyne
or reasons of safe transportation of fruits, mangoes, bananas etc are picked before they ripen fully. Slightly green harvested mangoes are subjected to small containers of calcium carbide (CaC2) with a plastic covering. CaC2 reacts with the moisture in the air to release acetylene (or ethyne) gas as follows:
CaC2 + 2 H2O → C2H2 + Ca(OH)2
This option may give you slightest confusion if you don’t know the difference between Ethylene and Ethyne (Acetylene). Both are chemical substances produced by fruits to accelerate the normal process of fruit maturation — is a ripening hormone. Ethylene is C2H4 and has a carbon-carbon double bond. Acetylene is C2H2 and has a carbon-carbon triple bind. Acetylene contains more energy and burns hotter than ethylene. Ethylene is a gaseous compound , Acetylene is the chemical compound , which is the simplest alkyne and is also a hydrocarbon while Ethylene is the simplest alkene and classified as an unsaturated hydrocarbon. I hope you will never forget it now.