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Question
Solve the following problem:
The hourly energy requirements of an astronaut can be satisfied by the energy released when 34 grams of sucrose are “burnt” in his body. How many grams of oxygen would be needed to be carried in space capsule to meet his requirement for one day?
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Solution
34 g of sucrose provides energy for an hour.
Hence, for a day, the mass of sucrose needed = 34 × 24 = 816 g
The balanced equation is,
\[\ce{\underset{\text{342 g}}{C12H22O11}_{(g)} + \underset{\text{12×32=384 g}}{12O2}_{(g)}->12CO2_{(g)} + 11H2O_{(l)}}\]
Thus, 342 g of sucrose require 384 g of oxygen.
∴ 816 g of sucrose will require = `816/342 × 384` = 916 g of O2
Astronaut needs to carry 916 g of O2
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