Final answer:
From the reaction 2H₂ + O₂ → 2H₂O, reacting 4.0 grams of hydrogen gas will yield 36.04 grams of water, considering we have enough oxygen for the reaction.
Step-by-step explanation:
The task is to determine how many grams of water are produced from reacting 4.0 grams of hydrogen gas based on the chemical reaction: 2H₂ + O₂ → 2H₂O.
First, we have to understand the stoichiometry of the reaction, which tells us that 2 moles of hydrogen gas will react with 1 mole of oxygen gas to produce 2 moles of water. The molar mass of hydrogen gas (H₂) is about 2.02 g/mol, so 2 moles of hydrogen gas weigh approximately 4.04 g.
Since we are starting with 4.0 g of hydrogen gas, we have approximately 2 moles of hydrogen available for the reaction. According to the balanced chemical equation, these 2 moles of hydrogen would produce 2 moles of water. Given that the molar mass of water (H₂O) is approximately 18.02 g/mol, the mass of 2 moles of water would be 36.04 g.
Thus, we can conclude that reacting 4.0 grams of hydrogen gas will yield 36.04 grams of water, assuming we have a sufficient amount of oxygen present to complete the reaction.