Chapter 2: (1) Basic Concepts of Matter Flashcards
Meaning of matter
Matter is something that has mass and occupies space
What are the 3 states of matter
Solid, Liquid, Gas
What is the definition of an element
A substance made from only one type of atom
What is the definition of compound
A substance made from two or more different elements
What is kinetic theory of matter
Tiny and discrete particles that make up matter are constantly moving. The higher the temperature, the higher the kinetic energy of the particles. Lighter particles move faster than heavier particles. Particles will move from high conc to low conc.
What is melting
The process where a solid changes to its liquid state at a certain temperature and pressure
What is melting point
The constant temperature when a substance changes from solid state to become liquid at a specific pressure
What is boiling
The process where a liquid changes to its gaseous state at a certain temperature and pressure
What is boiling point
The constant temperature when a substance changes from a liquid state to become gas at a specific pressure
What is freezing
The process where a liquid changes to its solid state at a certain temperature and pressure when it is cooled
What is freezing point
The constant temperature when a substance changes from liquid state to become solid at a specific pressure
What happens to the temp when a substance undergoes changes in physical state during MELTING process?
Temp remains unchanged because hear energy absorbed by the particles is used to overcome the attractive forces between particles so that the solid changes to a liquid.
What happens to the temp when a substance undergoes changes in physical state during FREEZING process?
Temp remains unchanged because heat energy released to the surroundings is balanced by the heat released when the liquid particles attract one another to form solid
Why do different substance have different melting and boiling points?
When the force of attraction between particles is stronger/weaker, more/less heat energy is needed to overcome the force. The melting and boiling points are higher/lower.
What is supercooling
A condition when a liquid is cooled too quickly and the temperature of a cooling liquid drops below the normal freezing point without changing to solid state.
