How many representative particles are in 6.8 g of H_2O?

1 Answer
Feb 4, 2017

"Number of particles" -= "Mass"/"Molar mass"xxN_A, where N_A="Avogadro's number", 6.022xx10^23.

Explanation:

I KNOW that an 18.01*g mass of water contains "Avogadro's number of molecules", i.e. 6.022xx10^23 INDIVIDUAL WATER molecules.

And thus the number of water molecules, i.e. representative particles, in a 6.8*g mass is:

(6.8*g)/(18.01*g*mol^-1)xx6.022xx10^23*mol^-1-="How many water molecules".