Enthalpy And Calorimetry Essay

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Recommended: Evaluating change in enthalpy

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…

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

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