Derive the molecular formula of an inorganic substance consisting of hydrogen and sulfur atoms if its relative

Derive the molecular formula of an inorganic substance consisting of hydrogen and sulfur atoms if its relative density for hydrogen is 17 and the mass fraction of sulfur is 94%.

Given:

w% (S) = 94%

D (H2) = 17

Find:

Formula -?

Solution:

1) Find the molecular weight of a compound by its hydrogen density:

D (H2) = Mr (UV): Mr (H2)

Mr (HC) = D (H2) * Mr (H2) = 17 * 2 = 34.

2) Knowing the mass fraction of sulfur in the compound, we find its molecular weight in the composition and the number of atoms:

34 – 100%

x – 94%,

then x = 94% * 34: 100% = 32.

N (S) = 32: Mr (S) = 32: 32 = 1 atom.

3) Then the molecular weight of hydrogen in the composition is 34 – 32 = 2.

N (H) = 2: Mr (H) = 2: 1 = 2 atoms.

We got a substance with the formula H2S – hydrogen sulfide.

Answer: H2S is hydrogen sulfide.