Question

For which of the following conversions does the value of the conversion factor depend upon the formula of the substance?

Answer 1

The answer is: C) mass of any substance to moles.

To converte mass to amount of substances, mass must be divided by molar mass (n = m ÷ M).

Molar mass M represent the mass of a substance divided by the amount of substance. If the formula is not correct, amount of substance is not correct.

For example, calculate molar mass of iron(II) chloride:

Atomic mass of iron is 55.8 g/mol.

Atomic mass of chlorine is 35.5 g/mol.

If compound is FeCl, molar mass would be 55,8 g/mol + 35,5 g/mol = 91,3 g/mlo, that is not correct.

If compound is FeCl₂, malar mass of compound would be:

55,8 g/mol + 2·35,5 g/mol = 126,8 g/mol, that is correct.

Answer 2

For which of the following conversions does the value of the conversion factor depend upon the formula of the substance?

The answer is C