2. Take small but equal amounts of water and milk in two different but similar containers. Freeze them by putting in a refrigerator. Now melt them in the sunshine, boil them on the same stove under the same conditions, and evaporate them completely. Note their temperature and time during changing of their states. What similarities and differences you find while changing the states of both of the materials. Support your investigation results with time and temperature graph.
Answers
Testing the Effect of Surface Area
Molecules contained in a liquid evaporate from the surface area. This means that the larger the surface area, the faster the rate of evaporation. Test this by putting water into two different containers. Use one that has a diameter of a 3 or 4 inches, such as a glass, and another that has a diameter of 8 to 10 inches, such as a bowl. Put 2oz of water into a measuring jug then transfer it to the glass. Do the same for the bowl and then place the containers next to each other. This means all the other factors that affect the rate of evaporation are identical. Leave the containers for one hour. Pour the water from each container into the measuring jug and write down how much water is left. The amount of water left in the bowl is much less than is left in the glass, due to the difference in surface area.