Answer:
39.7 %
Explanation:
magnesium + oxygen ⟶ magnesium oxide
10.57 g 6.96 g 17.53 g
According to the <em>Law of Conservation of Mass</em>, the mass of the product must equal the total mass of the reactants.
Mass of MgO = 10.57 + 6.96
Mass of MgO = 17.53 g
The formula for mass percent is
% by mass = Mass of component/Total mass × 100 %
In this case,
% O = mass of O/mass of MgO × 100 %
Mass of O = 6.96 g
Mass of MgO = 17.53 g
% O = 6.96/17.53 × 100
% O = 0.3970 × 100
% O = 39.7 %
Answer:
See explanation below.
Explanation:
In the equation ∆G = –nFE, E is the electromotive force ( cell potential ) in Volts.
Now in turn a Volt is defined as the potential difference that will impart one joule of energy per coulomb of charge that moves through two points.
V = J/C where J is Joules and C is coulombs of charge
Therefore in terms of units the equation will give us units of Joules:
[ mol] x [C/mol] x [J/C] = [J]
