A sample of toluene, C7H8 has a mass of 74.5 g.

Question

a) how many molecules does the sample contain?
b) How many carbon atoms does it contain? How many hydrogen atoms does it contain?

My work
For b would it be 7 carbon atoms and 8 hydrogen atoms

Answer 1

If it weighs any number of grams it has millions of atoms even if it is URANIUM!!!!!

6.02 * 10^23 molecules/mol
Avagadro's constant

7 C = 84 g/mol
8 H = 8 g/mol
so 92 g/mol

(74.5/92) * 6*10^23 = 4.86 *10^23 MOLECULES

7 times that many C atoms
8 imes that many H atoms

Answer 2

So would i multiply 4.86 x 10^23 by 7 to get the number of carbon atoms
And multiply by 8 to get the number of hydrogen atoms