To convert from grams to moles, you must divide the given mass by the molecular weight. If this is so, then:
Water ≈ 18.02 grams/mol.
85.0 g/ 18.02 g/mol ≈ 4.72 moles
Oxid # : 0 0 +2 -1

∴ the nickel was oxidized while chlorine was reduced
nickel reduction potential = - 0.25 V
but since it is being oxidised the you have to switch the integer sign so the
the potential of nickel in this case becomes + 0.25 V
chlorine was reduced thus its reduction potential remains same = + 1.36 V
Overall Cell potential = ∑ of half cell potential
The overall cell potential = (+ 1.36) + (+ 0.25)
= + 1.61 V
∴
the answer would be D
2H2O --> 2H2 + O2
The mole H2O:mole O2 ratio is 2:1
Now determine how many moles of O2 are in 50g: 50g × 1mol/32g = 1.56 moles O2
Since 1 mole of O2 was produced for every 2 moles of H2O, we need 2×O2moles = H2O moles
2×1.56 = 3.13 moles H2O
Finally, convert moles to grams for H2O:
3.13moles × 18g/mol = 56.28 g H2O
D) 56.28
Answer: 0.5 mol h2o
Explanation: Hope this help :D