Question

How many moles of aluminum, sulfur, and oxygen atoms are there in 7.00 moles of aluminum sulfate, `Al_2(SO_4)_3`?

Answer 1

`7.00` moles of `"Al"_2("SO"_4)_3"` contain `14.0` mol Al atoms, `21.0` mol S atoms, and `84.0` mol O atoms.

Explanation:

In one mole of aluminum sulfate, `"Al"_2"(SO"_4")"_3"`, there are 2 moles Al atoms, 3 moles sulfur atoms, and 12 moles O atoms.

To determine the number of moles of atoms of each element in 7.00 moles of the compound, multiply the number of moles times 7.00.

`"Al":` `7.00cancel("mol Al"_2("SO"_4)_3)xx(2"mol Al atoms")/(1cancel("mol Al"_2("SO"_4)_3))="14.0 mol Al atoms"`

`"S":` `7.00cancel("mol Al"_2("SO"_4)_3)xx(3"mol S atoms")/(1cancel("mol Al"_2("SO"_4)_3))="21.0 mol S atoms"`

`"O":` `7.00cancel("mol Al"_2("SO"_4)_3)xx(12"mol O atoms")/(1cancel("mol Al"_2("SO"_4)_3))="84.0 mol O atoms"`