The molar mass of fluorine is 19.00 g/mol and that of aluminium is 26.98 g/mol. How do you calculate the molar mass of aluminium fluoride?

1 Answer
Mar 13, 2017

Answer:

The molar mass of aluminium fluoride is 83.98 g/mol.

Explanation:

The formula of aluminium fluoride is #"AlF"_3#.

This tells us that one formula unit of #"AlF"_3# contains one atom of #"Al"# and three atoms of #"F"#.

It also tells us that one mole of contains one mole of #"Al"# atoms and three moles of #"F"# atoms.

Thus, we can calculate the molar mass of #"AlF"_3# as follows:

#"Mass of 1 mol" = 1 color(red)(cancel(color(black)("mol Al"))) × "26.98 g"/(1 color(red)(cancel(color(black)("mol Al")))) + 3 color(red)(cancel(color(black)("mol F"))) × "19.00 g"/(1 color(red)(cancel(color(black)("mol F")))) = "26.98 g + 57.00 g" = "83.98 g"#