Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Section 2-4 TEST
science: study physical and chemical changes
| Question | Answer |
|---|---|
| Definition of physical change | altars a substance but does not change it into another substance. ex: paper when you tear it |
| Definition of chemical change | it is changed into another substance with different properties. ex: burning wood |
| Definition of thermal energy | The total energy of a substances particles due to their movement or vibration |
| Definition of chemical energy | The energy stored within chemical bonds within matter |
| Whats true about changes in matter? | Matter changes whenever energy is added or taken away |
| What is the principle that says in every physical or chemical change the total amount of energy stays the same? | Law of Conservation of Energy |
| The change in state from solid to a liquid is called | melting |
| in most pure substances, melting occurs at a temperaturethat is specific to the substance, called the | melting point |
| the change in state from a liquid to a solid is called | freezing |
| T or F? When the temperature of water drops to 0 degrees C, its molecules form regular patterns, which are crystals | True |
| the change in state from the liquid to the gas state of matter is called | Vaporization |
| Vaporization includes... | evaporation whic occurs on the surface of the liquid; and boiling which occurs throughout the liquid |
| each liquid boils only at a certain temperature, which is called | boiling point |
| Why is the boiling point of water lower in the mountains than it is at sea level? | In the mountains, air pressure is lower, and so is the boiling point |
| The change in state from a gas to a liquid is called | condensation |
| T or F? Condensation is the opposite of vaporization. | True |
| When condensation occurs, does gas lose or gain thermal energy? | loses thermal energy |
| Example of vaporization | liquid water changes into vapor |
| Example of evaporation | a puddle dries up after a rain shower |
| Example of boiling | a pot of water on a stove reaches its boiling point |
| Example of condensation | clouds form from water vapor in the sky |
| The change in state from a solid directly to a gas without passing through the liquid state is called | sublimation |
| T or F? Changes in state are example of chemical changes. | False; physical |
| Whats true about chemical reactions? | -all chemical reactions either absorb or release energy -in some chemical reactions, two or more substances combine, forming one or more new substances -all chemical reactions form new substances |
Created by:
Yael
Popular Science sets