3.1 Changes of state and particle model Flashcards
What is the definition of density?
State the relevant equation with units.
The mass per unit of volume of volume.
p=mv
Density (kg/m^3), mass (kg), volume (m^3)
State the different states of matter in order (least to most) of density of atoms.
Gas, liquid, solid
Describe the particle arrangement of a solid
Tightly packed in a regular arrangement. Particles can only vibrate on the spot.
Describe the particle arrangement of a liquid
Close, but with an irregular arrangement. They can flow over each other.
Describe the particle arrangement of a gas
Separated, with no regular arrangement. Particles can move freely.
What is always conserved when a substance undergoes a state of change?
Mass
How does a change of state differ from a chemical change?
In a change of state, the material can return to having its previous properties if the change is reversed.
What is sublimation?
When a solid changes into a gas without passing through a liquid state
What is evaporation?
When a liquid changes into a gas state
What is the opposite of evaporation?
Condensation, which is when a gas changes into a liquid state
When water boils in an open pan, why does the mass of the pan of water appear to decrease?
Some of the water will evaporate and turn into water vapour. This will leave the pan meaning the mass of the pan will decrease. The mass of the whole system however remains constant.
Explain the processes involved when a bathroom mirror mists up
Hot water evaporates to form water vapour, this water vapor lands on the cooler mirror. The vapor condenses and returns to liquid state on the mirror’s surface.
