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Question
A gas occupies 500 cm3 at a normal temperature. At what temperature will the volume of the gas be reduced by 20% of its original volume, the pressure is constant?
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Solution
V = 500 cm3
Normal temperature, t = 0°C = 0 + 273 K
V1 = Reduced volume + 20% of 500 cm3
`= (20 xx 500)/100 = 100 "cm"^3`
Net, V1 = 500 - 100 = 400 cm3
T1= ?
P = P1
Using gas equation,
`"PV"/"T" = ("P"_1 "V"_1)/"T"_1`
`("P" xx 500)/273 = ("P" xx 400)/"T"_1`
T1 = `(273 xx 4)/5 = 218.4 "K"`
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Match the following:
|
|
Column A |
Column B |
|
(a) |
cm3 |
(i) Pressure |
|
(b) |
Kelvin |
(ii) Temperature |
|
(c) |
Torr |
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|
(d) |
Boyle's law |
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|
(a) |
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(v) `"PV"/"T" = ("P"_1 "V"_1)/"T"_1` |
|
|
|
(vi) PV = P1V1 |
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