Question

A compound has an empirical formula of c2h4s. its molar mass was determined experimentally to be 179g/mol. what is the molecular formula for this compound?

Answer 1

To determine the molecular formula of a compound with empirical formula C2H4S and molar mass 179g/mol, calculate the molar mass of the empirical formula, find the ratio between the empirical and experimental molar masses, and then multiply the subscripts in the empirical formula by this ratio to obtain the molecular formula, which is C6H12S3.

Step-by-step explanation:

The question is asking us to determine the molecular formula of a compound given its empirical formula and molar mass. The empirical formula represents the simplest whole-number ratio of the elements in the compound, and the molecular formula represents the actual number of atoms of each element in a molecule of the compound.

To find the molecular formula from the empirical formula, we first calculate the molar mass of the empirical formula, then divide the experimental molar mass of the compound by this number to find the ratio between them. The ratio should be a simple whole number or close to it, and this number will be used to multiply the subscripts in the empirical formula to get the molecular formula.

For the compound in question, let's calculate the empirical formula mass: Carbon (C) has an atomic mass of about 12.01 g/mol, Hydrogen (H) is approximately 1.01 g/mol, and Sulfur (S) is approximately 32.07 g/mol. The empirical formula C2H4S gives us a mass of 2(12.01 g/mol) + 4(1.01 g/mol) + 32.07 g/mol = 24.02 g/mol + 4.04 g/mol + 32.07 g/mol = 60.13 g/mol. The experimental molar mass of the compound is given as 179 g/mol. Dividing the molecular molar mass by the empirical formula molar mass (179 g/mol / 60.13 g/mol) gives us approximately 2.98, which we round to 3 to get a whole number ratio.

Therefore, by multiplying the subscripts in the empirical formula by 3, the molecular formula for the compound is C6H12S3.

Answer 2

To find the molecular formula for a compound with an empirical formula of C2H4S and molar mass of 179 g/mol, we can compare the molar mass of the empirical formula to the actual molar mass. The molecular formula is C6H12S3.

Step-by-step explanation:

To find the molecular formula for a compound, we need to know both the empirical formula and the molar mass. The empirical formula gives us the relative ratio of atoms in the compound, while the molar mass tells us the actual mass of the compound. In this case, the empirical formula is C2H4S and the molar mass is 179 g/mol. We can determine the molecular formula by comparing the molar mass of the empirical formula to the actual molar mass.

The molar mass of C2H4S is calculated as:

Carbon: 2(12.01 g/mol) = 24.02 g/mol

Hydrogen: 4(1.01 g/mol) = 4.04 g/mol

Sulfur: 1(32.07 g/mol) = 32.07 g/mol

Total molar mass of C2H4S = 60.13 g/mol

To find the ratio of the actual molar mass to the molar mass of the empirical formula, we divide the actual molar mass (179 g/mol) by the molar mass of the empirical formula (60.13 g/mol).

Molecular formula = (179 g/mol) / (60.13 g/mol) = 2.97

Since the ratio is close to 3, we can multiply the empirical formula by 3 to get the molecular formula.

Molecular formula = 3(C2H4S) = C6H12S3