How many electrons are present in one molecule of CH₄?

Identify the longest carbon chain and mention the number of carbons present in it.

Gas M occupies a volume of 1000 c.c and contains X molecules. How many molecules will be present in gas N occupying a volume of 250 c.c?

Element X belongs to period 2 and group 1 of the periodic table. State the formula of the chloride of the element X.