Answer:
The amount (mass) of water we will have is 17.869 grams
Explanation:
The molar mass of hydrogen gas H₂ = 2.016 grams/mole
The molar mass of oxygen gas = 31.999 g/mol
Therefore, 2.00 g of hydrogen will give;
2.00/2.016 = 0.9921 moles of H₂ gas and
15.87 g of O₂ will give;
15.87/31.999 = 0.49595 moles
The reaction is as follows;
2H₂ (g) + O₂ (g) → 2H₂O (l)
Two moles of H₂ react with one mole of O₂ to produce two moles of H₂O
Therefore 0.9921 moles of H₂ will react with 0.9921/2 or 0.49595 moles of O₂ to produce 0.9921 moles of H₂O
From the above we note that all the H₂ and O₂ are completely consumed to form 0.9921 moles of H₂O
Molar mass of H₂O = 18.01528 g/mol
Number of moles = Mass/(Molar mass)
∴ Mass of H₂O = (Molar mass) × (Number of moles)
= 18.01528 g/mol × 0.9921 moles = 17.869 grams
Therefore the amount (mass) of water we will have = 17.869 grams.