Derive the formula for a substance containing 60% carbon, 13.33% hydrogen, the rest is oxygen

| June 19, 2021 | education

Derive the formula for a substance containing 60% carbon, 13.33% hydrogen, the rest is oxygen, and having a relative density for He equal to 15

Knowing the relative density of matter D by helium (15), we can calculate the molar mass of an unknown substance by multiplying D by the molar mass of helium.

M (He) = 4 g / mol

M = 15 * 4 = 60 g / mol

Mass fraction of element X in the compound is calculated by the following formula:

w (X) = n * A (X) / Mr,

where n is the number of atoms of element X in the compound,

Mr is the relative molecular weight of the compound.

Knowing Mr and w (X), we calculate n carbon, oxygen and hydrogen.

n (C) = w (C) * Mr / A (C) = 0.60 * 60/12 = 3

n (O) = w (O) * Mr / A (O) = 0.2667 * 60/16 = 1

n (H) = w (H) * Mr / A (H) = 0.1333 * 60/1 = 8

The simplest compound formula: C3H8O or C3H7OH – propanol.



One of the components of a person's success in our time is receiving modern high-quality education, mastering the knowledge, skills and abilities necessary for life in society. A person today needs to study almost all his life, mastering everything new and new, acquiring the necessary professional qualities.