It is known that hydrogen with a volume of 1 dm3 contains the same number of atoms as oxygen with

It is known that hydrogen with a volume of 1 dm3 contains the same number of atoms as oxygen with a volume of 1 dm3. The density of hydrogen is 0.09 g / dm3, and the density of oxygen is 1.43 g / dm3. Calculate how many times the mass of a hydrogen atom is less than the mass of an oxygen atom.

Given:
V (H2) = 1 dm ^ 3
V (O2) = 1 dm ^ 3
N (H) = N (O)
ρ (H2) = 0.09 g / dm ^ 3
ρ (O2) = 1.43 g / dm ^ 3

Find:
m (O) / m (H) -?

Solution:
1) Find the mass of the substance H2 and O2:
m (H2) = ρ (H2) * V (H2) = 1 * 0.09 = 0.09 g;
m (O2) = ρ (O2) * V (O2) = 1 * 1.43 = 1.43 g;

2) Find the amount of substance H2 and O2:
n (H2) = m (H2) / Mr (H2) = 0.09 / 2 = 0.045 mol;
n (O2) = m (O2) / Mr (O2) = 1.43 / 32 = 0.045 mol;

3) Find the amount of substance H and O (by definition):
n (H) = n (H2) * 2 = 0.045 * 2 = 0.09 mol;
n (O) = n (O2) * 2 = 0.045 * 2 = 0.09 mol;

4) Find the mass of H and O:
m (H) = n (H) * Mr (H) = 0.09 * 1 = 0.09 g;
m (O) = n (O) * Mr (O) = 0.09 * 16 = 1.44 g;

5) Find the ratio of the masses of H and O:
Since the number of H and O atoms is the same, then
m (O) / m (H) = 1.44 / 0.09 = 16.

Answer: The mass of the H atom is 16 times less than the mass of the O atom.