Required Practical 2 Flashcards
How is the accurate temperature determined for the enthalpy change?
1) Plot a graph of temperature on the y-axis and time on the x-axis.
2) Draw two separate best fit lines. One which connects the points before the addition and one which connects the points after the addition.
3) Extrapolate both lines to the fourth minute.
4) Determine the temperature change at this point.
What are potential errors in the apparatus?
Heat transfer to or from the surroundings.
It is assumed that all solutions have the heat capacity of water and no heat is absorbed by the calorimeter.
Incomplete combustion if using a fuel.
How can the accuracy of the experiment be improved?
An electronic temperature sensor could be used to get more precise results.
A bomb calorimeter could be used to reduce the heat energy lost to the surroundings.
Why is a lid used on the calorimeter?
It minimises heat lost to the surroundings and maximises the change in temperature.
