5 moles of oxygen are heated at constant volume from `10^(@)C` to `20^(@)C`. The change in internal energy of a gas.
`[C_(P)=7.03 cal mol^(-1) deg^(-1)` and `R=8.3J mol^(-1) deg^(-1)]`

Explanation

`R=8.31J" "mol^(-1)deg^(-1) and R=8.31" J "mol^(-1)`
`=1.99" cal "mol^(-1)deg^(-1)`
We know that `C_(P)-C_(V)=R`
or `C_(V)=C_(P)-R=7.03-1.99=5.04cal" "mol^(-1)deg^(-1)` ltBrgt Heat absorbed by 5 mole of oxygen in heating from `10^(@)C` to `20^(@)C`
`=5xxC_(V)xxDeltaT=5xx5.04xx10=252`cal
Since, the gas is heated at constant volume, no external work is done,
i.e., So, change in internal energy will be equal to heat absorbed,
`DeltaU=q+w=252+0=252`cal