Question | Answer |
What is a water molecule made up of? | Two hydrogen atoms and one oxygen atom. |
Why don't water drops break apart easily? | Water molecules are attracted to each other. |
Why do two water drops easily combine into one when they are brought near each other? | Water molecules are attracted to each other. |
Why does a drop of food coloring spread throughout water without stirring? | Water molecules are in motion and cause the food coloring to spread. The food coloring molecules are also in motion. |
What happens to water molecules when a sample of water is heated? | The water molecules begin to move faster and spread further apart. |
solid | *Certain shape and size (volume)
*Molecules arranged close together, usually in a pattern
*Molecules vibrate while staying in position
*Motion is slowest of all three states |
liquid | *Takes the shape of its container
*Certain size (volume)
*Molecules are close together, but randomly arranged
*Molecules move faster than in a solid and slide past each other |
gas | *Takes the shape and size (volume) of its container
*Molecules are spread apart (random)
*Molecules move the fastest of all three states |
humidity | The amount of water vapor in the air. Air that contains a lot of vapor can feel damp. Your skin may also feel sticky and wet because of the amount of water vapor. |
water vapor | Water in the form of a gas. |
evaporation | The change of state from a liquid to a gas. Evaporation occurs when heat is added and molecules begin to move faster and spread apart. |
condensation | The change of state from a gas to a liquid. Condensation occurs when heat is removed and molecules begin to slow down and move closer together. |
melting | The change of state from a solid to a liquid. Melting occurs when heat is added and molecules begin to move faster and spread apart. |
freezing | The change of state from a liquid to a solid. Freezing occurs when heat is removed and molecules begin to slow down and move closer together. |