What effect has impurities on the melting and boiling points of pure substances? illustrate your answer with an example pls need it by tonight ​

The presence of an impurity in a substance lowers the melting point, and raises the boiling point of the substance. For example, Impurities present in the water decrease the freezing temperature of the water, and in the same way, impurities increase the boiling point of the water.

the molecules move in straight line until they collide with each other or with the walls of the container. collisions are perfectly elastic; when two molecules collide, they change their directions and kinetic energies, but the total kinetic energy is conserved.

explanation:

answer: c. the experiment shows that the red substance experienced a chemical change.

explanation: chemical change is the change in which chemical composition of the substance changes. physical change is the change in which there is no change in chemical composition.

chemical changes are accompanied by following changes:

a) precipitate formation

b) energy is released or absorbed

c) formation of bubbles

d) change in color

as it is given that the red color has disappeared and there is production of gas, it means the red substance has undergone a chemical change.

e