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Question
The difference between the two molar specific heats of gas is 9000 J/kg K. If the ratio of the two specific heats is 1.5, calculate the two molar specific heats.
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Solution
Given,
Cp - Cv = 9000 J/kg K
`"C"_"p"/"C"_"v" = 1.5`
Cv = ?
Cp = ?
`"C"_"p"/"C"_"v" = 1.5`
`"C"_"p" = 1.5 " C"_"v"`
`"C"_"p" - "C"_"v" = 9000`
`1.5 " C"_"v" - "C"_"v" = 9000`
`0.5 " C"_"v" = 9000`
`therefore "C"_"v" = 9000/0.5`
= 18000 J/kg k
`therefore "C"_"p" = 9000 + "C"_"v"`
= 9000 + 18000
= 27000 J/kg k
∴ Two molar specific heats ore 18000 J/kg k and 27000 J/kg k.
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