During the free expansion of an ideal gas in an isolated chamber,

An ideal gas absorbs $210 \ J$ of heat and undergoes expansion from $3 \ L$ to $6 \ L$ against a constant external pressure of $10^5 \ Pa$. What is the value of $\Delta U$ (in $J$)?

$A$ gas expands isothermally against a constant external pressure of $1 \ bar$ from $10 \ dm^3$ to $20 \ dm^3$ by absorbing $800 \ J$ of heat from the surroundings. Calculate the value of $\Delta U$. (in $J$)

According to the first law of thermodynamics,which of the following is correct? (Where $q =$ heat supplied to the system and $W =$ work done by the system)

The $\Delta U^o$ of combustion of $CH_{4(g)}$ at a certain temperature is $-393 \ kJ/mol$. Then the value of $\Delta H^o$ is:

What is the internal energy change when $X \ J$ of work is done on the system and $Y \ J$ of heat is transferred to the surrounding?