$2.5 \ kJ$ of work is done on the system and it releases $1500 \ J$ of heat. What is the change in internal energy (in $J$)?

Assuming all reactions occur in an open vessel,for which reaction will $\Delta H = \Delta U$?

Calculate the change in internal energy of the system if $37.6 \ J$ of work is done by the system with heat loss of $14.6 \ J$ (in $J$)?

At $300 \ K$,the enthalpy change for the reaction $C_3H_8(g) + 5O_2(g) \rightarrow 3CO_2(g) + 4H_2O(l)$ is $-2800 \ kJ \ mol^{-1}$. Calculate the internal energy change $(\Delta U)$ for the reaction at the same temperature.

For an isochoric process,the first law of thermodynamics can be expressed as:

Calculate the change in internal energy of the system if $25 \ kJ$ of work is done by the system and it absorbs $10 \ kJ$ of heat. (in $kJ$)