 # Enthalpy And Calorimetry Essay

explanatory Essay
940 words
940 words Introduction: This lab has to do with enthalpy and calorimetry. Enthalpy is a measure of the amount of energy in a system, which is the part of the universe we are studying. Equation one is used to find enthalpy. (Equation 1) ΔH=E +PV In this equation, ΔH is the change in heat, E is energy, P represents pressure, and V is volume. The change in enthalpy is synonymous with the change in heat. If the change in enthalpy is positive, it is an endothermic reaction. A negative answers means it is an exothermic reaction. Equation two is the equation for the enthalpy of a reaction. (Equation 2) Hrxn= Hproducts - Hreactants Calorimetry is used to measure enthalpy. It measures how much heat is flowing. The equation for calorimetry is equation number …show more content…

#### In this essay, the author

• Explains that equation one is used to find enthalpy and calorimetry, which measures the amount of energy in a system.
• Explains that h is the change in heat, e is energy, p represents pressure, and v is volume. equation two is for the enthalpy of a reaction.
• Explains that calorimetry is used to measure enthalpy. it measures how much heat is flowing.
• Explains that the initial and final temperatures were found for each trial (table 1). these results were averaged, and equation three was used to determine the grams used.
• Explains how the grams of each salt used in the experiment were divided by the change in temperature recorded. equation 4 was used to determine the price.
• Explains that \$0.75, \$0.36, and \$0.19 were used because they cover the cost of the plastic bag, labor and overhead costs.
• Explains the lab's goal to determine which two salts would be best to make a profitable hot and cold pack.
• Explains that styrofoam cup calorimeters will be used for this lab. each packet must be stored at room temperature, cost less than five dollars, and contain a salt and water.
• Explains that the lab lab requires room temperature water, spoons, digital scale, graduated cylinder, plastic boats, styrofoam cups, and a lab quest temperature probe.

These results were averaged (table two). If the final temperature was less than the initial temperature, it will be used as a cold pack. If it is greater, it will be used as a hot pack. To determine the amount of grams used, equation three was used. (Equation 3) G1/ΔT1 = G2/ΔT2 In this equation, the grams of each salt used in the experiment was divided by the change in temperature recorded in the experiment. This was set equal to the amount of grams you would need to reach 65º C or 0º C divided by the temperature change needed to reach the desired temperature. After the amount of grams needed was determined, the price must be found. Equation 4 was used to determine the price. (Equation 3) \$0.75 + \$0.36 + \$0.19 + (P/500) * G \$0.75, \$0.36, and \$0.19 were used because they cover the cost of the plastic bag, labor, and overhead costs. P represents the price of the salt per five hundred grams provided by the company. G is how many grams are needed to reach the desired temperature. The results can be found in table three. (Table 3) Grams Needed and Cost Name of Compound Grams Needed (g) Cost