Which type of reaction i.e. addition or substitution is shown by ethyne and ethene?

Q. Addition reactions and substitution reactions are types of organic reactions. Which type of reaction is shown by :
(ii) ethene​

Q. What are addition reactions? How are addition reactions of ethene different from ethyne?

Q. Addition reactions and substitution reactions are types of organic reactions. Which type of reaction is shown by :
(i) ethane​

Q. Explain the following:
(i) Ethene and ethyne burn with a sooty luminous flame.
(ii) Ethane does not undergo addition reactions.
(iii) Ethyne is used for welding and cutting metals.

Q. Choose the correct answer:
The formation of 1, 2-dibromoethane from ethene and bromine is an example of:
(a) Substitution
(b) Dehydration
(c) Dehydrohalogenation
(d) Addition