RP 02- Measurements of a enthalpy change

Chemistry

Why might an experimental value for enthalpy change be different to the theoretical value?

Heat loss to apparatus / surroundings

Incomplete combustion

Non-standard conditions

Evaporation of alcohol / water

How do you prevent heat loss to surroundings / apparatus?

Insulate the beaker by placing it in a polystyrene cup with a lid

Avoid larger temperature differences between the surroundings and calorimeter

Use a bomb calorimeter

Other than preventing heat loss, how can the accuracy of this experiment be improved?

Stir the solution so the temperature is evenly distributed

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