# Analysis: Joe Science Vs. The Water Heater

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Thermodynamics is essentially how heat energy transfers from one substance to another. In “Joe Science vs. the Water Heater,” the temperature of water in a water heater must be found without measuring the water directly from the water heater. This problem was translated to the lab by providing heated water, fish bowl thermometers, styrofoam cups, and all other instruments found in the lab. The thermometer only reaches 45 degrees celsius; therefore, thermodynamic equations need to be applied in order to find the original temperature of the hot water. We also had access to deionized water that was approximately room temperature.
Two equations were used in this experiment to determine the initial temperature of the hot water. The first equation …show more content…

First, 100 mL of regular deionized water was measured using a 100 mL graduated cylinder. This water was then poured into the styrofoam cup that will be used to gather the hot water later. The water level was then marked using a pen on the inside of the cup. The water was then dumped out, and the cup was dried. Next, 100 mL of regular deionized water was measured using a 100 mL graduated cylinder, and the fish tank thermometer was placed in the water. Once the temperature was stabilizing in the graduated cylinder, the marked styrofoam cup was filled to the mark with hot water. Quickly, the temperature of the regular water was recorded immediately before it was poured into the styrofoam cup. The regular/hot water was mixed for a couple seconds, and the fish tank thermometer was then submerged into the water. After approximately 30 seconds, the temperature of the mixture leveled out, and was recorded. This was repeated three …show more content…

This is by using the same mass and realizing that the specific heat of both the regular water and the hot water are the same. In our procedure, 100 mL of hot water was mixed with 100 mL of the regular water; therefore, the masses in Equation 3 cancel out (the densities of the water at different temperatures aren’t exactly the same, but the difference is negligible). This leads to the change in temperature of the hot water equaling the negative change of temperature in the regular water, shown as: (4)
Using Equation 4, it can be inferred that the initial temperature of the hot water minus the change in temperature of the mixture equals the temperature of the cold water plus the change in temperature of the mixture (Equation 5). This is then rearranged to indicate that the initial temperature of the hot water is two times the change in temperature plus the initial temperature of the regular water. This is shown in Equation 6.