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Tag: enthalpy
Learn how to plan an investigation and select the correct variables to control with this experiment to determine the enthalpy change for the reaction MgSO4 (s) + 7H2O(l) → MgSO4•7H2O(s) using Hess cycles. By measuring the enthalpy change of solution for the two solids and using a Hess cycle to calculate the enthalpy change for the reaction, we can gain a better understanding of thermodynamic principles.
In this experiment, the aim is to determine the heats of combustion of alcohols, specifically butan-1-ol. The experiment involves burning a measured mass of an alcohol in a spirit lamp and transferring the heat energy released to a calorimeter containing water. From the resulting temperature rise, the heat of combustion can be calculated. The apparatus used must be calibrated using an alcohol with a known heat of combustion due to factors such as the heat energy lost to the surrounding air and the heat capacity of the calorimeter. Safety precautions must also be taken due to the flammability and potential toxicity of the alcohols. The experiment provides an opportunity to calculate the specific heat capacity of the calorimeter and determine the enthalpy change of butan-1-ol. Calculations can be made to determine the percentage difference between experimental values and data book values and to explain why there may be a difference.
In this chemistry experiment, we aim to determine the enthalpy change for the displacement reaction between zinc and copper sulfate solution. By measuring the temperature change over a period of time and using calculations, we can obtain the enthalpy change and thermochemical equation for the reaction. The procedure involves adding excess zinc powder to the solution and recording the temperature every 30 seconds for 8 minutes. We also discuss how to calculate the percentage error and possible reasons for differences between the experimental and accepted values. This experiment is a great opportunity to learn about enthalpy, displacement reactions, and thermochemistry in practice.
In this experiment, you'll be measuring the heat of combustion of a series of five primary alcohols, from methanol to pentanol. By burning a measured mass of an alcohol in a spirit lamp and transferring the heat energy released to a calorimeter containing water, you'll be able to calculate the heat of combustion. The experiment requires safety glasses, a thermometer, a calorimeter, and the primary alcohols, which are flammable and potentially poisonous. Once completed, you'll be able to plot a graph of your results and draw conclusions from the data.
Practical Science 