Answer:
Mole fraction O₂= 0.43
Explanation:
Mole fraction is the moles of gas/ total moles.
Let's determine the moles of each:
Moles O₂ → 15.1 g / 16 g/mol = 0.94
Moles N₂ → 8.19 g / 14 g/mol = 0.013
Moles H₂ → 2.46 / 2 g/mol = 1.23
Total moles = 2.183
Mole fraction O₂= 0.94 / 2.183 → 0.43
Mass of copper : 0.165 g
<h3>Further explanation</h3>
Given
5.0 A over 100 seconds
Required
Mass of copper
Solution
Faraday's law:
<em>The mass of the substance formed at each electrode is proportional to the electric current flowing in the electrolysis</em>
<em />
<em />
e = Ar / valence = eqivalent weight
i = current
t = time
W = weight
CuSO₄ ----> Cu²⁺ + SO₄²⁻
Cu ----> Cu²⁺ + 2e
e = Ar/2
= 63,5/2 = 31,75

The final gas pressure : 175.53 atm
<h3>Further explanation</h3>
Maybe the complete question is like this :
A ridged steel tank filled with 62.7 l of nitrogen gas at 85.0 atm and 19 °C is heated to 330 °C while the volume remains constant. what is the final gas pressure?
The volume remains constant⇒Gay Lussac's Law
<em>When the volume is not changed, the gas pressure in the tube is proportional to its absolute temperature </em>

P₁=85 atm
T₁=19+273=292 K
T₂=330+273=603 K
