MCQ : A sample is known to contain 2 × 6.022 × 10^23 hydrogen atoms. How many hydrogen atoms does it contain?

Question

A sample is known to contain 2 × 6.022 × 10²³ hydrogen atoms. How many hydrogen atoms does it contain?

1. 1 mol
2. 1\over 2 mol
3. 2 mol
4. N_A mol

Answer

2 mol

Explanation

To determine the number of hydrogen atoms in the sample in terms of moles, we can use Avogadro’s number as a conversion factor:

n = N\over N_A

where n is the number of moles, N is the number of particles, and NA is Avogadro’s number.

Substituting the values given in the problem, we get:

n = 2 × 6.022 × 10^{23} \over 6.022 × 10^{23}  

Simplifying, we get:

n = 2

Therefore, the sample contains 2 moles of hydrogen atoms.