Question

1-How does the Law of Conservation of Energy explain why ice cubes melt in water?

2-What are the two differences between mass and weight?

3-Why does an object’s weight change on the moon but its mass stays the same?

4-Explain how two objects that have the same mass can have different densities.

5-How can you tell if a mixture is homogeneous (solution) or heterogeneous (not a solution)?
6-Identify each of the following examples below as either a homogeneous mixture (solution) or a heterogeneous mixture.
7-What are 3 methods you can use to separate a mixture? Give an example of each.
8-What is the difference between an atom and a molecule?
9-Is a compound a mixture or a pure substance?
10-How are elements arranged on the Periodic Table? by increasing
atomic number.

Answer 1

Answer: 1.The water molecules in the liquid phase have more energy than the molecules in the solid phase. The reason that the ice melts is that some of the energy in the water is transferred to the ice – this provides the heat necessary for the transition from the solid to liquid phase