The molar mass of ammonium acetate is 77.083 g/mol. A student uses 0.100 mol of ammonium acetate in a chemical reaction. The student claims that the reaction uses ( 0.100 mol ) ( 77.083 g/mol ) = 7.71 g of ammonium acetate, which has ( 7.71) (6.022 X 10^23) = 4.64 X 10^24 molecules.

Question

The molar mass of ammonium acetate is 77.083 g/mol. A student uses 0.100 mol of ammonium acetate in a chemical reaction. The student claims that the reaction uses ( 0.100 mol ) ( 77.083 g/mol ) = 7.71 g of ammonium acetate, which has ( 7.71) (6.022 X 10^23) = 4.64 X 10^24 molecules.

In one to two sentences, explain the mistake that the student made and determine the correct number of molecules of ammonium acetate used in the reaction.

Answer 1

The mistake the student made is that they used Avogadro's number to convert grams to molecules, which is only applicable for counting particles (atoms, molecules) and not for converting grams to molecules. The correct number of molecules used in the reaction is (0.100 mol) x (6.022 x 10^23 molecules/mol) = 6.02 x 10^22 molecules.