Identify a statement that is incorrect about alkanes.
(i) They are hydrocarbons. (ii) There is single covalent bond between carbon and hydrogen. (ii) They can undergo addition as well as substitution reactions. (iv) On complete combustion with oxygen, they produce carbon dioxide and water

Explanation

To solve the question, we need to evaluate each of the provided statements about alkanes and identify which one is incorrect.

1. **Statement (i): They are hydrocarbons.**
- Alkanes are indeed hydrocarbons, which means they are compounds made up solely of carbon (C) and hydrogen (H) atoms. This statement is correct.

2. **Statement (ii): There is a single covalent bond between carbon and hydrogen.**
- In alkanes, the bonds between carbon and hydrogen are single covalent bonds. For example, in ethane (C2H6), each carbon atom is bonded to hydrogen atoms through single bonds. This statement is also correct.

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