Answer:
To determine how many grams of O₂ are required to produce 36 g of H₂O, we need to use stoichiometry and balance the chemical equation first:
_2_H₂ + _1_0₂ --> _2_H₂O
The balanced chemical equation indicates that 1 mole of O₂ reacts with 2 moles of H₂ to produce 2 moles of H₂O.
To find the moles of H₂O produced from 36 g of it, we can use its molar mass:
Molar mass of H₂O = 18.015 g/mol
36 g / (18.015 g/mol) = 1.998 mol of H2O
Since 2 moles of H₂O are produced from every 1 mole of O₂, we will need half as many moles of O₂:
1.998 mol of H₂O / 2 = 0.999 mol of O₂
To convert moles of O₂ to grams, we use its molar mass:
Molar mass of O₂ = 32 g/mol
0.999 mol of O2 * 32 g/mol = 31.97 g or approximately 32 g of O₂ (rounded to two significant figures) is needed to produce 36 g of H₂O.