Answer:
No the substance is not water.
Explanation:
The balance chemical equation for the decomposition of water is as follow;
2 H₂O = 2 H₂ + O₂
Step 1: Calculate moles of H₂O;
Moles = Mass / M.Mass
Moles = 5.0 g / 18.01 g/mol
Moles = 0.277 moles of H₂O
Step 2: Calculate Moles of O₂ and H₂ produced by 0.277 moles of H₂O:
According to equation,
2 moles of H₂O produced = 1 mole of O₂
So,
0.277 moles of H₂O will produce = X moles of O₂
Solving for X,
X = 0.277 mol × 1 mol / 2 mol
X = 0.138 moles of O₂
Also,
According to equation,
2 moles of H₂O produced = 2 mole of H₂
So,
0.277 moles of H₂O will produce = X moles of H₂
Solving for X,
X = 0.277 mol × 2 mol / 2 mol
X = 0.227 moles of H₂
Step 3: Calculate Mass of O₂ and H₂ as;
For O₂:
Mass = Moles × M.Mass
Mass = 0.138 mol × 31.99 g/mol
Mass = 4.44 g of O₂
For H₂:
Mass = Moles × M.Mass
Mass = 0.227 mol × 2.01 g/mol
Mass = 0.559 g of H₂
Conclusion:
From conclusion it is proved that the amount of H₂ produced by decomposition of 5 g of water should be 0.559 g while in statement it is less i.e. 0.290 g.
