Final answer:
To determine how much oxygen reacted to produce 294g of water when 32.9g of hydrogen burned, subtract the mass of hydrogen from the mass of water to get the mass of the oxygen. The calculated mass of oxygen that reacted is 261.1g.
Step-by-step explanation:
To find out how much oxygen reacted when 32.9g of hydrogen burned to produce 294g of water, we can use the conservation of mass and the stoichiometry of the balanced chemical equation. The balanced equation for the reaction of hydrogen with oxygen to form water is:
2 H₂(g) + O₂(g) → 2 H₂O(g)
Following the law of conservation of mass, the mass of the reactants equals the mass of the products. Since the mass of the hydrogen is given as 32.9g, and we have produced 294g of water, we can calculate the mass of oxygen that reacted by subtracting the mass of hydrogen from the mass of water produced.
Mass of water (H₂O) - Mass of hydrogen (H2) = Mass of oxygen (O2)
294g - 32.9g = 261.1g
Therefore, 261.1g of oxygen reacted with hydrogen to produce 294g of water.