PROBLEM ONE $(4$ MARKS$)$:

Write and simplify the closed system energy balance for each of the following processes. State

whether non$-$zero heat and work terms are positive or negative.

a$)$ A closed flask with water is heated from $30\backslash$deg C to $65\backslash$deg C

b$)$ A tray filled with water at $15\backslash$deg C is placed in a freezer and turns to ice at $-4\backslash$deg C

c$)$ A chemical reaction takes place in a closed adiabatic rigid container

d$)$ A chemical reaction takes place in a closed rigid container. The system is isothermal, but there

is a temperature change associated with the reaction that occurs.