how will you convert ethene into methane?

Answer 1

Ethene, C(2)H(4) contains a double bond between Carbons and is relatively unstable compared to CH(4), which contains only single bonds. A brute force method would be to apply heat (raising the temperature) to rupture the double bond to produce the more stable methane. As a practical consequence, however, recall that methane, as a gas, is combustible.

Answer 2

You boil it until the 'm' falls off

Answer 3

add one carbonium