Question

Let's assume you are given two glass jars. Jar #1 has 32.07 g of sulfur and Jar #2 has 112.4 g of cadmium (Cd). Which beaker contains the greatest number of atoms? Choose the best answer.

a. Jar #1 because one sulfur atom weighs less than one cadmium atom so you need more of the sulfur atoms to fill the jar.

b. Jar #1 because it contains more moles of sulfur atoms than the number of moles of cadmium atoms in Jar #2.

c. Jar #2 because cadmium has a greater mass than sulfur.

d. Jar #2 because it contains more moles of cadmium atoms than the number of moles of sulfur atoms in Jar #1.

e. Jars #1 and #2 contain the same number of atoms because there is one mole in each.

Answer 1

Jars #1 and #2 contain the same number of atoms because there is one mole in each.

The molar masses of S and Cd are 32 g/mol and 112 g/mol respectively. Thus, 32 g of S and 112 g of Cd corresponds to 1 mole each. 1 mole of any substance contains avogadro's number of atoms which is $6.023 \times 10^{23}$ atoms.