When water gets solidified into ice,then heat is

Which is the correct statement?

Ravi added a small amount of common salt to water taken in a graduated cylinder. On dissolution,there was no detectable change in the level of water. Explain why this is so.

Give a reason why gas exerts pressure on the walls of the container.

Name the states of matter that:
$(a)$ have a definite shape,volume,and mass.
$(b)$ have the minimum force of attraction between the particles.
$(c)$ have the maximum force of attraction between the particles.

How do the following factors affect the rate of evaporation of a liquid?
$(a)$ Surface area
$(b)$ Temperature
$(c)$ Humidity