The measurement of the hotness or coldness of a substance is known as its temperature. It determines the direction of the flow of heat when two bodies are placed in contact.
Activity: To find the temperature of a boiling water
Materials Required:
  1. Vessel
  2. Thermometer
  3. Water
  4. Stove (Heat source)
  • Take a vessel and fill it with water.
  • Keep the vessel on the stove.
  • Fix the thermometer over the water as shown below.
Fig. - Experiment to find the temperature of a boiling water
  • Observe the reading in the thermometer and tabulate it.
The thermometer should not touch the vessel in which the water is being heated. Otherwise, the thermometer will be broken at a high temperature.
You will be able to see that,
  • The water starts to boil,  when the temperature of water reaches to \(100\)°\(C\).
  • The temperature of the boiling water does not rise further after \(100\)°\(C\).
Boiling Point of water:
When boiling water is heated for some time, it continues to receive more heat, but its temperature does not rise further. The point at which the water boils and temperature becomes stable is called the boiling point of water.