Source: Ketron Mitchell-Wynne, PhD, Asantha Cooray, PhD, Department of Physics & Astronomy, School of Physical Sciences, University of California, Irvine, CA

When a pot of water is placed on a hot stove, heat is said to "flow" from the stove to the water. When two or more objects are placed into thermal contact with each other, heat spontaneously flows from the hotter objects to the colder ones, or in the direction that tends to equalize the temperature between the objects. For example, when ice cubes are put in a cup of room-temperature water, heat from the water flows to the ice cubes and they begin to melt. Often, the term "heat" is used inconsistently, usually to simply refer to the temperature of something. In the context of thermodynamics, heat, like work, is defined as a transfer of energy. Heat is energy transferred from one object to another because of a difference in temperature.

Furthermore, the total energy of any isolated thermodynamic system is constant-that is, energy can be transferred to and from different objects within the system and can be transformed to different types of energy, but energy cannot be created or destroyed. This is the first law of thermodynamics. It is very similar to the conservation of energy law discussed in another video, but in the context of heat and thermodynamic processes. In the case of ice cubes in water, if the first law of thermodynamics was invalid, then one might expect that adding ice cubes to an isolated room-temperature cup of water would cause the water to boil, which would imply the creation of energy.

1. Measure the specific heat capacity of lead and demonstrate the first law of thermodynamics.

1. Obtain a scale, a lead sample, two Styrofoam cups, a 300-mL (or larger) beaker, a heating element, a thermometer, a piece of string, water at room temperature, a rod attached to stand with clamps, a graduated cylinder, and scissors.
2. Cut a small portion off the top of one of the Styrofoam cups so that it can act as a lid for the other cup. Make a small hole in the bottom, large enough for the thermometer to

Using the values recorded in Table 1, the specific heat of lead can be calculated. From the first law of thermodynamics, it is known that energy is neither created nor destroyed in an isolated system, but energy can transfer between different objects within the system. When the hot piece of lead is put in the coffee cup calorimeter, heat will be supplied from the lead to the water, and that heat transfer is conserved; that is, the heat output of the lead, Q