Question

Calculate the following quantities. (See the periodic table.)
(a) mass, in grams, of 2.54 10-2 mol of CdS


g

(b) number of moles of NH4Cl in 90.0 g of this substance


mol

(c) number of molecules in 5.081 10-2 mol C6H6


molecules

(d) number of O atoms in 4.72 10-3 mol Al(NO3)3

Answer 1

You need to remember two formula for this. For mass, g, mols, it is
mols = grams/molar mass. That will do a and b.

For # molecules, remember that 1 mol of anything contains 6.02E23 of those anythings. That will do c and d.