The molar mass of hydrogen [tex]\left( H_2 \right)[/tex] is [tex]2.02 \, \text{g/mol}[/tex]. A sample contains [tex]4.00 \, \text{mol}[/tex] of [tex]H_2[/tex]. What is the mass, in grams, of this sample?

A. 1.98 grams
B. 2.02 grams
C. 4.00 grams
D. 8.08 grams



Answer :

To determine the mass of the hydrogen sample in grams, we need to use the concept of molar mass. The molar mass is the mass of one mole of a substance. Here we are dealing with hydrogen gas (H₂), which has a molar mass of 2.02 grams per mole.

Given:
- Molar mass of H₂ = 2.02 g/mol
- Number of moles of H₂ = 4.00 mol

The relationship between mass, molar mass, and moles is given by the formula:
[tex]\[ \text{Mass} = \text{Molar Mass} \times \text{Number of Moles} \][/tex]

Plugging in the given values:
[tex]\[ \text{Mass of H₂ sample} = 2.02 \, \text{g/mol} \times 4.00 \, \text{mol} \][/tex]

Calculating this product, we get:
[tex]\[ \text{Mass of H₂ sample} = 8.08 \, \text{grams} \][/tex]

Therefore, the mass of the hydrogen sample is 8.08 grams.

So, the correct answer is:
[tex]\[ 8.08 \, \text{grams} \][/tex]