Hi! We already finished this lab for calorimetry, but I'm not sure how to complete this question. Thanks for the help!
Briefly describe the three assumptions made in carrying out this experiment. Compare your calculated enthalpy of formation of (NH4)2SO4(s) to the actual enthalpy of formation value (-1180 kJ/mol). Based on this comparison, comment as to whether or not the three assumptions are valid and comment on any potential sources of error.
These are the assumptions from the lab
"In carrying out this experiment, we were required to assume that the calorimeter used was completely insulated and prevented heat from being lost or gained (for the surroundings). We also assumed that the solution’s density and heat capacity were the same as the heat capacity (4.184𝐽/ 𝑔∙°𝐶) and density of water (1.00𝑔/𝑚L). Furthermore, it was assumed by those carrying out the experiment that the reaction took place in an open-aired environment with constant pressure conditions where the reaction vessel is not completely secured."
To complete this question, you need to describe the three assumptions made in carrying out the experiment and compare the calculated enthalpy of formation of (NH4)2SO4(s) to the actual enthalpy of formation value. Then, comment on whether or not the assumptions are valid and discuss any potential sources of error.
1. The first assumption made in the experiment is that the calorimeter used was completely insulated and prevented heat from being lost or gained to the surroundings. This assumption ensures that the heat exchange only occurs between the reaction mixture and the calorimeter itself.
2. The second assumption is that the solution's density and heat capacity were the same as the heat capacity (4.184 J/g∙°C) and density of water (1.00 g/mL). This assumption allows for easy and accurate calculations of the heat capacity and enthalpy changes.
3. The third assumption is that the reaction took place in an open-aired environment with constant pressure conditions where the reaction vessel is not completely secured. This assumption implies that the pressure remains constant during the reaction, which simplifies the calculations of enthalpy changes.
To compare the calculated enthalpy of formation of (NH4)2SO4(s) to the actual enthalpy of formation value (-1180 kJ/mol), you need to calculate the enthalpy change using the data obtained in the experiment. Then, compare this value to the actual enthalpy value and calculate the percent difference.
To determine if the assumptions are valid, you can consider whether they have significant impacts on the results. If any of the assumptions are found to be invalid, it could affect the accuracy and reliability of the calculated enthalpy change.
As for potential sources of error, they could include measurement errors, incomplete reactions, heat loss to the surroundings despite insulation, variations in the atmospheric pressure, or experimental uncertainties associated with equipment and techniques used.
By analyzing the calculated enthalpy of formation compared to the actual value and considering the validity of the assumptions and potential sources of error, you can provide a comprehensive comment on the accuracy and reliability of the experiment.