How to Calculate the Number of Moles in a Substance

19 Sep 2021

How many moles of CaCO3 are there in 2.50*10^24 molecules of CaCO3?

A. 4.16 × 10^7 moles

B. 2.50 × 10^24 moles

C. 7.81 × 10^15 moles

D. 5.02 × 10^20 moles

The correct answer is A. 4.16 × 10^7 moles.

To calculate the number of moles in a substance, you can use the formula:

moles = no of molecules ÷ Avogadro's number

Given that there are 2.50 × 10^24 molecules of CaCO3, you can calculate the number of moles as follows:

moles = 2.50 × 10^24 ÷ 6.02 × 10^23

moles ≈ 4.16 × 10^7

Therefore, there are approximately 4.16 × 10^7 moles of CaCO3 in 2.50 × 10^24 molecules of CaCO3.