Because in SI, the expectation is that area and volume will be expressed in terms of a linear dimension( the metre) or its multiples.
You can tell the difference by How shiny it is and by how heavy it is
Explanation:
here is the answer to your question
The molar mass of aluminum sulftae is 342.14 g/mol.
Since the subscript shows that there are 3 sulfurs within the substance, the total mass of sulfur is 96.21g/mol
Now take the mass of the sulfur and divide it by the molar mass of aluminum sulfate, then multiply by 100:
(96.21/342.15)(100) = 28.1% mass composition of sulfate
