Question

Air consists of molecules of several types, with an average molar mass of 28.95 g. An adult who inhales 0.6 L of air at sea level takes in about how many molecules? (The density of air is 1.229 kg/m^3, and the molar mass of air is 28.95 g/mol.)

Answer 1

0.6 L = 6*10^-4 m^3
The mass of that volume is
6*10^-4*1.229 kg , which is
0.737 grams.
Divide that by 28.95 g/mol for the number of moles. Then multiply that by Avogadro's number for the number of molecules.

Answer 2

tyvm :)