Question

A sample of crushed rock is found to have 4.81 x10^21 atoms of gold. How many moles of gold are present in this sample?

Answer 1

To calculate the number of moles of gold in the sample, divide the number of atoms of gold by Avogadro's number.

Step-by-step explanation:

To determine the number of moles of gold in the sample, we need to use Avogadro's number, which states that there are 6.022 x 10^23 atoms in 1 mole of any substance. Given that the sample contains 4.81 x 10^21 atoms of gold, we can calculate the number of moles using the formula:

moles of gold = number of atoms of gold / Avogadro's number

moles of gold = 4.81 x 10^21 atoms / 6.022 x 10^23 atoms/mol

After performing the calculation, we find that there are approximately 0.0798 moles of gold in the sample.

Answer 2

0.8 moles

Step-by-step explanation:

To find the number of moles in a substance given it's number of entities we use the formula

`n = (N)/(L) \\`

where n is the number of moles

N is the number of entities

L is the Avogadro's constant which is

6.02 × 10²³ entities

We have

`n = \frac{4.81 * {10}^(23) }{6.02 * {10}^(23) } = (4.81)/(6.02) \\ = 0.799003...`

We have the final answer as

0.8 moles

Hope this helps you