Determine the number of hydrogen molecules if its mass in the cylinder is 400 g.

Determine the number of hydrogen molecules if its mass in the cylinder is 400 g. The molar mass of hydrogen molecules is 2 g / mol.

The number of hydrogen atoms can be calculated using the formula:
N = υ * Na, where υ is the amount of substance (mol), Na is Avogadro’s number (Na = 6 * 10 ^ 23 mol ^ -1).
Amount of substance:
υ = m / M, where m is the mass of hydrogen (m = 400 g = 0.4 kg), M is the molar mass of hydrogen (M = 2 g / mol = 0.002 kg / mol).
Let’s calculate the number of hydrogen atoms:
N = υ * Na = m * Na / M = (0.4 * 6 * 10 ^ 23) / 0.002 = 1200 * 10 ^ 23 = 1.2 * 10 ^ 26.
Answer: The number of hydrogen atoms is 1.2 * 10 ^ 26.