You are part of a group of tourists stranded on a deserted island, and you need to distill seawater to obtain drinking w

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You are part of a group of tourists stranded on a deserted
island, and you need to distill seawater to obtain drinking water.
Distillation involves vaporizing the liquid, and then re-condensing
it; doing this leaves nonvolatile components (such as sea salt)
behind and produces pure water. You are fortunate enough to have
found some coal, which you can use to power your distillery. Coal
burns according to the equation: C(s) + O2(g) → CO2(g). The heat of
combustion of coal is 32.5 kJ/g. You can obtain seawater at 28.0o
C, and it boils at 100.7o C. It has a specific heat of 3.9 J/go C,
and a heat of vaporization of 2143.7 J/g. You need to vaporize
100.0 kg of water for yourself and your companions to survive. What
mass of coal will you need to burn? Assume 100% efficient use of
the heat produced by the coal.