Take a bowl of ice, put it out in direct sunshine and note its temperature after every 05 minutes. What type of change in its temperature, do you observe? How much time will it take to melt completely? Now put the same water on a stove and note down its temperature after every 30 seconds. What type of change in its temperature, do you observe now? How much time will it take to boil? Explain your observations with the help of time and temperature chart. (Perform this experiment on a sunny day)
Answers
Answer:
when we put the bowl of ice outside, we observe that there's no change in temperature while it's melting.
we can call it as latent heat of fusion
- latent heat of fusion:The amount of heat energy required in the process of melting for a unit mass of solid to be converted into liquid.
so , the temperature reamins constant as the energy is spent in changing the State of solid into liquid. so when the water is in zero degree temperature same as ice temperature.
when we put the same water in stove .
we can observe that the temperature is increasing according to the time .
when the water temperature reaches 100⁰ ,we can observe that there's no change in temperature . this is called boiling.
the energy of heat that water get is not used for increasing in temparature but used for increasing of movement of molecules inside the water and creates bubbles filled with air that form on the surface of the water and finally the bubbles pops and release gases into atmosphere .
so in this while this constant temperature of heating is called latent heat of vapourization.
latent heat of vapourization:The heat required to change 1 g of a liquid at its boiling point to vapor at the same temperature.
hope this helps