Calculate `DeltaU and DeltaH` in calories if one mole of a monoatomic ideal gas is heated at constant pressure of 1 atm from `25^(@)C` to `50^(@)C`.

Explanation

For an ideal gas, the changes in internal energy `(DeltaU)` and enthalpy `(DeltaH)` due to the change in its temperature are givenn by the relations
`DeltaU=nC_(V,m)DeltaT and DeltaH=nC_(P,m)DeltaT`
For a monoatomic ideal gas, `C_(V,m)=(3)/(2)R and C_(P,m)=(5)/(2)R`.
the number of mole of the gas, n=1, and the change in temperature `(DeltaT)=25K`
Therefore `DeltaU=1xx(3)/(2)Rxx25=1xx1.5xx1.987xx25cal`
`=74.51cal`
and `DeltaH=1xx(5)/(2)Rxx25=1xx2.5xx1.987xx25cal=124.18cal`