Question

What conversion factor is use to convert 3 moles of magnesium mg to grams?

Answer 1

The question requires us to provide the conversion factor by which we can transform 3 moles of magnesium (Mg) into its correspondent mass, in grams.

The conversion factor is the number we use to multiply a value in order to convert it from one unit to another (in this case, from moles to grams).

To answer this question, we should remember that the number of moles of a substance is defined as the ratio of its mass (in grams, g) by its molar mass (in grams per mol, g/mol):

`n=(m)/(M)`

(where n is the number of moles, m is the mass and M is the molar mass)

Rearranging the equation above, we find that the mass of a substance is its number of moles multiplied by its molar mass:

`m=n* M`

Therefore, to find the mass of 3 moles of magnesium, we can simply multiply the number of moles (3 mol) by magnesium molar mass (24.31 g/mol):

`m_(Mg)=(3\text{ mol)}*(24.31\text{ g/mol) = }72.93\text{ g}`

The conversion factor in the calculation above, where we transformed 3 moles of magnesium in its correspondent mass, is the molar mass of magnesium, 24.31 g/mol.