Final answer:
To burn 106.3 g of diborane (B₂H₆), 368.64 g of liquid oxygen (LOX) would be required. This is calculated based on the stoichiometry of the balanced chemical combustion reaction.
Step-by-step explanation:
To calculate the mass of liquid oxygen (LOX) needed to burn 106.3 g of diborane (B₂H₆), we must first use the balanced chemical equation for the combustion of diborane:
B₂H₆ (g) + 3 O₂ (g) → 2 HBO₂ (g) + 2 H₂O (l)
From the equation, we can see that 1 mole of B₂H₆ reacts with 3 moles of O₂. First, determine the molar mass of B₂H₆ which is (2 × 10.81) + (6 × 1.008) = 27.7 g/mol. Now, divide the given mass of B₂H₆ by its molar mass to get the number of moles of B₂H₆:
106.3 g B₂H₆ × (1 mol B₂H₆/27.7 g) = 3.84 moles of B₂H₆
Now calculate the moles of O₂ required using the stoichiometry of the reaction (3 moles of O₂ per mole of B₂H₆):
3.84 moles of B₂H₆ × 3 moles O₂/1 mole B₂H₆ = 11.52 moles O₂
Finally, calculate the mass of O₂ using the molar mass of O₂ which is (2 × 16.00) = 32.00 g/mol:
11.52 moles of O₂ × 32.00 g/mol = 368.64 g of O₂
So, 368.64 g of LOX would be needed to burn 106.3 g of diborane (B₂H₆).