Question

19 While heating ice in a beaker with a thermometer suspended in it, a student recorded the following observations: Time (in min) Temp (in °C) 0 -3 1 2 0 3 0 4 5 5 8 6 12 7 15 8 19 10 22 15 30 20 50 25 73 30 100 35 100 Based on the above observations, answer the following questions: (0) State the change(s) observed between 2 min to 3 min and name the process involved. (10) Define latent heat of fusion. (iii) Explain why there is no change in the temperature from 30 min to 35 min? (iv) Give one point of difference between evaporation and boiling.​

Answer 1

Answer:

Between 2-3 min, ice converts into water. This process is known as fusion. Between 30-35 min, the temperature remains constant because the heat supplied is used up in overcoming the intermolecular forces of liquid to change into vapours.

The amount of heat required to change 1 g of a substance at the temperature of its melting point from the solid to the liquid state without changing temperature.

Evaporation is a normal process that occurs when the liquid form changes into the gaseous form; while causing an increase in the pressure or temperature. Boiling is an unnatural process where the liquid gets heated up and vaporized due to continuous heating of the liquid.