Question

I need some help on this question please!

A chemist has 3.45 x 1022 molecules of P2O5. How many grams of P2O5 does the chemist have?

Thanks to anyone who helps!

Answer 1

8.12 g

Step-by-step explanation:

The molar mass of P2O5 is 141.94 g/mol. Since one mole contains Avogadro’s number (6.022 x 10^23) of molecules, the chemist has (3.45 x 10^22) / (6.022 x 10^23) = 0.0572 moles of P2O5.

Therefore, the chemist has 0.0572 moles * 141.94 g/mol = 8.12 grams of P2O5.

or

You have 3.45 x 10^22 molecules of P2O5.

1 mole = 6.022 x 10^23 molecules

So, you have 3.45 x 10^22 molecules / 6.022 x 10^23 molecules/mol = 0.57 mol P2O5

The molar mass of P2O5 is 159.89 g/mol

So, you have 0.57 mol P2O5 x 159.89 g/mol = 8.12 g P2O5