Answer: We know that, 1 mole of any substance contain 6.022 X 10^23 atoms/molecules. Thus, 2.14 moles are present in 1.29x10^24 hydrogen atoms in HF.
Explanation:
divide it by avogadro's constant
that is 6.02 × 10²³
1.2 × 10²⁴ / 6.02 × 10²³
= 2 mol
