Answer:
3.01 x 10²¹
Explanation:
Molar mass of h₂o =18.01528 g/mol.
it means 1 mole h₂o=18.01528 g .....(1)
1 mole = 6.022 × 10^23 molecules
so,
1 mole h₂o =6.022 × 10^23 molecules=18.01528 g [from 01]
now,
18.01528 g h₂o has= 6.022 × 10^23 molecules
9.00x10⁻² g h₂o has= ( 6.022 × 10^23 x 9.00x10⁻² ) /18.01528 molecules
=3.008 x 10²¹ molecules
≈ 3.01 x 10²¹ molecules
I am not completely sure what your question is, but I think you are asking about the molar mass? It is a mole conversion. For example, if you start with atoms and want grams, you would need to get rid of the atoms unit first then get rid of the mols unit: so you would have to multiply it by (1 mol / Avogadro's number) X (molar mass / 1 mol) = this is the conversion factor that gives you grams. I hope this helped!
Have a fantastical day,
Em
<span>Tropical fossils in Antarctica.</span>
DeltaH formation = deltaH of broken bonds - deltaH of formed bonds
Broken bonds: tiple bond N-N and H-H bond
Formed bonds: N-H and N-N bonds
You also have to take note of the molar coefficients
deltaH formation = <span> [(N≡N) + 2 * (H-H)] - [4 * (N-H) + (N-N)]
= (945 + 2*436) - (4*390 + 240)
= 17 kJ/mol
The answer is 17 kJ/mol.</span>