Matter & Heat Flashcards
What is meant by an “Element”?
A substance made of only one type of atom.
What is meant by a “Molecule”?
Two (or more) atoms chemically joined together.
What are the three states of matter ?
- Solids
- Liquids
- Gases
What is meant by “Density” ?
It is a measure of how much matter is within a volume. Measured in kg / m³
How are the atoms arranged in a solid ?
The atoms are in tightly packed, fixed position, vibrating on the spot.
How are the atoms arranged in a liquid ?
The atoms are tightly packed, but free to move past each other, taking the shape of the bottom of their container.
How are the atoms arranged in a gas ?
The atoms are far apart and free to move past each other, taking the shape of the whole of their container.
Can a solid be compressed ?
No, the atoms are too tightly packed.
Can a liquid be compressed ?
No, the atoms are too tightly packed.
Can a gas be compressed ?
Yes, the atoms are far apart and can be compressed into a smaller volume.
What is meant by “Boiling” ?
Changing state from a liquid to a gas.
What is meant by “Condensing” ?
Changing state from a gas to a liquid.
What is meant by “Freezing”
Changing state from a liquid to a solid.
What is meant by “Melting” ?
Changing state from a solid to a liquid.
Is heat energy released or absorbed when “Freezing” ?
Released.
Is heat energy released or absorbed when “Melting” ?
Absorbed
Is heat energy released or absorbed when “Boiling” ?
Absorbed
Is heat energy released or absorbed when “Condensing” ?
Released
What is meant by “Heat” ?
A form of energy, associated with vibrating atoms or molecules. Measured in Joules ( J )
What is meant by “Temperature” ?
A measure of how “hot or cold” a substance is. Measured in degrees Celcius ( °C )
What is meant by “Conduction” ?
Transfer of heat energy through a solid, by causing particles to vibrate more.
What is meant by “Convection” ?
Transfer of heat moving through a fluid (liquid or gas) moving in a convection current.
What is meant by a “Convection current”?
Hot, less dense fluid rising and cooler, denser fluid sinking.
What is meant by “Radiation”?
Transfer of heat moving as electromagnetic radiation (Infra-Red Radiation)
