Question

How many moles are 1.20 x 10^25 atoms of phosphorus?

a) 0.20 moles
b) 2.0 moles
c) 20 moles
d) 200 moles

Answer 1

To determine the number of moles, use Avogadro's number and calculate (number of atoms) divided by (Avogadro's number). The correct answer is option d) 200 moles.

Step-by-step explanation:

To determine the number of moles, we use Avogadro's number, which states that 1 mole of any substance contains 6.022 x 10^23 atoms. To calculate how many moles are in 1.20 x 1025 atoms of phosphorus, you need to use Avogadro's number, which is 6.022 x 1023 atoms per mole. The calculation is as follows:

Number of moles = Number of atoms ÷ Avogadro's number.

Given that there are 1.20 x 10^25 atoms of phosphorus, we can calculate the number of moles as follows:

Moles = (number of atoms) / (Avogadro's number)

Moles = (1.20 x 10^25) / (6.022 x 10^23) = 1.993 moles

Therefore, the correct answer is option d) 200 moles.