Suppose you were to make a ring from a single strand of gold atoms. How many gold atoms would be required to make such a ring? How much would the ring weigh in grams?

Let us assume that the ring is a size 7 ring, which has a circumference of 54.3 millimeters. Converting this to centimeters, the circumference of the ring is:

54.3 mm = 5.43 cm

Now, we determine the number of gold atoms that will be present in this:

5.43 / 1 x 10⁻⁹

There will be 5.43 x 10⁹ atoms

We now determine the number of moles this is by:

one mole = 6.02 x 10²³ atoms

Moles = 5.43 x 10⁹ / 6.02 x 10²³

Moles = 9.01 x 10⁻¹⁵ moles

The molar mass of gold is 197 g/mol

The mass is 9.01 x 10⁻¹⁵ * 197

The mass of the strand is 1.76 x 10⁻¹² grams