That's the answer on that picture
First, find moles of gold given the mass of the sample:
(35.9g Au)/(197.0g/mol Au) = 0.182mol Au
Second, multiply moles of Au by Avogrado's number:
(0.182mol)(6.02 x10^23)= 1.10x10^23 atoms Au
Answer:
1, 3, 2
Explanation:
N2 + H2 → NH3
I usually find that the best way to systematically balance an equation by inspection is to start with the most complicated-looking formula and then balance atoms in the order:
- All atoms other than O and H
- O
- H
(a) The most complicated formula is NH3.
(b) Balance N.
We have 1 H in NH3, but 2 N on the left. We need 2 N on the right. Put a 1 in front of N2 and a 2 in front of NH3.
1N2 + H2 → 2NH3
(c) Balance H.
We have fixed 6 H on the right, so we need 6 H on the left. Put a 3 in front of H2.
1N2 + 3H2 → 2NH3
The equation is now balanced, and the coefficients are 1, 3, 2.
