The carbon dioxide exhaled in the breath of astronaut is often removed from the spacecrafts by reaction with lithium hydroxide. 2LiOH(s) + CO 2 (g) → Li 2 CO 3 (s) + H 2 O(l) Assume that each astronau

Question

The carbon dioxide exhaled in the breath of astronaut is often removed from the spacecrafts by reaction with lithium hydroxide.

2LiOH(s) + CO₂(g) → Li₂CO₃(s) + H₂O(l)

Assume that each astronaut requires 2820 kJ of energy per day. Further assume that this energy is obtained only from the combustion of glucose into CO₂(g) and H₂O(l). The standard enthalpies of formation of glucose, CO₂ and water are -1260, -395 and -285 kJ/mol, respectively. The minimum mass (in g) of LiOH required per astronaut per day to react completely with all the CO₂ produced is

TestHub · Accepted Answer

ΔH comb (glucose) = [6(-395) + 6(-285)] - (-1260) = -2820 kJ/mol. Energy needed = 2820 kJ, so n glucose = 1.00 mol and n CO2 = 6.00 mol. LiOH needed = 2 × 6.00 = 12.0 mol = 12.0 × 23.94 ≈ 287 g. Answer: 0287.

Chemistry - Thermochemistry Question with Solution | TestHub

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