Final answer:
To react with 28.5 grams of hydrogen gas, 3619.5 grams of iodine are required according to the stoichiometry of the balanced chemical equation H2(g) + I2(g) = 2 HI(g).
Step-by-step explanation:
The student's question involves calculating the amount of iodine required to react completely with a given mass of hydrogen gas according to the chemical equation H2(g) + I2(g) = 2 HI(g). To find this, we first calculate the moles of hydrogen gas using its molar mass, then use stoichiometry to find the required moles of iodine, and finally convert the moles of iodine to grams using its molar mass.
Since the molar mass of hydrogen gas (H2) is approximately 2 grams per mole, 28.5 grams of hydrogen gas is equivalent to 14.25 moles of H2. According to the balanced chemical equation, 1 mole of H2 reacts with 1 mole of I2. Therefore, 14.25 moles of H2 will react with 14.25 moles of I2. The molar mass of iodine (I2) is approximately 254 grams per mole, so the mass of iodine required is 14.25 moles × 254 grams/mole = 3619.5 grams of iodine.