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Question
What temperature would be necessary to double the volume of a gas initially at s.t.p. if the pressure is decreased by 50%?
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Solution
P1 = 1 atm
P2 = `1 xx 50/100 = 1/2` atm
V1 = x cc
V2 = 2x cc
T1 = 273 K
T2 = ?
Using gas equation `("P"_1"V"_1)/"T"_1 = ("P"_2"V"_2)/"T"_2`
∴ T2 = `("P"_2"V"_2"T"_1)/("P"_1"V"_1)`
`"T"_2 = 1/2 xx (2"x" xx 273)/(1 xx "x") = 273` K
T1 = 273 - 273 = 0°C
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