Question

Please solve q 124?

Answer 1

The answer is `option (4)`

Explanation:

the molar concentration of the hydrogen is the number of moles found in a litre.

here, it is given that `20g` of hydrogen are found in `5l` of the vessel.

if `20g` are found in `5l`, then `4g` are found in `1l`.

to calculate the number of moles in `4g` of hydrogen, use the equation

`n = m/M`

where `n` is number of moles,

`m` is mass in grams

and `M` is molar mass in grams per mole.

the atomic mass of hydrogen is `1`.

Molecular mass of hydrogen `=2g`

`m/M = (4g)/(2 g//mol)`

`= 2 mol`

there are `2` moles of hydrogen present in `1l` of the vessel.

hence, the molar concentration is `2`.