Question

Find the mass of -
A) 15.055×10^23 atoms of Na
B) 3.011×10^23 molecules of NH^3
C) 0.025 moles of CaCO^3
D) 0.04 moles of CO^2

Answer 1

We know that ....
1 mole of atoms = 6.022× 10 ^23 atoms
so
6.022x10^23 atoms = 1 mole
1 atoms = 1/6.022×10^23 mole
3.011x10^23 atoms =
=3.011 ×10^23/6.022×10^23
=1/2 mole
and we also know that ....
1 mole of atom = atomic weight
so.
1 mole of nitrogen.= 14 grams
1/2 mole of nitrogen = 1/2x 14 =7grams
so..mass of nitrogen atom = 7grams..ans