|Initial temp. of solution (oC)||Maximium temp. of solution (oC)||Temperature rise (oC)
Note: mass of 50 cm3 of solution is 50 g
The cup used is polystyrene because:
polystyrene is an insulator which reduces heats loss
EXPERIMENT2: Combustion reactions
To measure the amount of energy produced when a fuel is burnt, the fuel is burnt and the flame is used to heat up some water in a copper container
Example: ethanol is burnt in a small spirit burner
- The initial mass of the ethanol and spirit burner is measured and recorded.
- 100cm3 of water is transferred into a copper container and the initial temperature is measured and recorded.
- The burner is placed under of copper container and then lit.
- The water is stirred constantly with the thermometer until the temperature rises by, say, 30 oC
- The flame is extinguished and the maximum temperature of the water is measured and recorded.
- The burner and the remaining ethanol is reweighed. For example:
|Mass of water (g)||Initial temp of water (oC)||Maximum temp of water (oC)||Temperature rise (oC)||Initial mass of spirit burner + ethanol (g)||Final mass of spirit burner + ethanol (g)||Mass of ethanol burnt (g)
The amount of energy produced per gram of ethanol burnt can also be calculated: