How many neon atoms in a 15.8g mass of neon gas?

3 Answers
Jan 8, 2018

See below..

Explanation:

No. of moles =Given massAtomic Mass= 15.820=0.79

No. of atoms = (Avogadro's no.) (no. of moles)=
(6.02210230.79)=4.751023

Jan 8, 2018

Well, we know that there are 6.022×1023 particles in a mole of such particles....

Explanation:

And we also know (do we?) that a 20.18g mass of neon gas contains 6.022×1023 individual neon atoms....

And so we work out the quotient multiplied by the Avocado number....

15.8g20.18gmol1×6.022×1023mol1

4.5×1023individual neon atoms...

Here I have used Avogadro's number precisely as I would any other collective number: dozen; Bakers' dozen; score; gross...

We use Avogadro's number because we know that such a number of neon atoms has a mass of 20.18g...

Jan 8, 2018

4.711023 atoms

Explanation:

Neon has an atomic mass of 20.18. Divide 15.8 grams by the atomic mass to determine the moles of Ne. Then multiply the moles of Ne by Avogadro's number to get the number of atoms.

(15.8g÷20.18 moles)6.021023 atoms = 4.711023 atoms