Assuming that the final (equilibrium) temperature of the system is above the melting point of ice, such that all ice in the container melts in this process thus
and
Let the final temperature of the system be . Thus
(converted to kilojoules)
The fact that energy within this system (assuming proper insulation) conserves allows for the construction of an equation about variable .
Confirm the uniformity of units, equate the two expressions and solve for :
which goes against the initial assumption. Implying that the final temperature does <em>not</em> go above the melting point of water- i.e., . However, there's no way for the temperature of the system to go below ; doing so would require the removal of heat from the system which isn't possible under the given circumstance; the ice-water mixture experiences an addition of heat as the hot block of lead was added to the system.
The temperature of the system therefore remains at ; the only macroscopic change in this process is expected to be observed as a slight variation in the ratio between the mass of liquid water and that of the ice in this system.
Energy may exist in different forms such as potential energy when a body is at rest, kinetic energy when the body is in motion, etc.
Energy can neither be created nor destroyed, however, it can be transformed from one form to another. For example, chemical energy may be transformed into mechanical energy or other forms of energy.