Properties of Materials Flashcards
(17 cards)
What does the particle model explain?
The properties of solids and fluids (liquids and gases)
The particle model describes how particles behave in different states of matter.
How is density calculated?
density = mass/volume
Density is a measure of how much mass is contained in a given volume.
What are the units for density?
g/cm³ or kg/m³
These units measure mass per unit volume.
What are the three states of matter?
Solid, liquid, and gas
These states can change when substances are heated or cooled.
What happens to a liquid when it evaporates?
It evaporates from its surface
Evaporation occurs at any temperature, but it is faster at higher temperatures.
What occurs when a liquid is boiling?
Bubbles of gas form within the liquid
Boiling occurs when the liquid reaches its boiling point.
What is unique about the melting point and freezing point of a substance?
They are the same temperature
The temperature remains constant during the phase change.
What happens to substances when they are heated?
They expand
Particles vibrate more and take up more space.
What happens to substances when they cool down?
They contract
Particles have less kinetic energy, reducing volume and increasing density.
What is unusual about ice compared to liquid water?
Ice is less dense than liquid water
This is why ice floats on water.
How does pressure in fluids act?
It acts in all directions
Pressure is caused by particles moving and colliding with surfaces.
What increases the pressure of a gas in a container?
- Having more particles in the container
- Heating the gas
- Reducing the volume of the container
These factors increase the frequency and force of collisions with the container walls.
What happens to pressure in a liquid with increasing depth?
Pressure increases
More water above exerts more weight and pressure.
What determines if an object will float or sink?
The density of the object compared to the density of the fluid
Objects with density less than the fluid will float.
What is the density of water?
1 g/cm³
Objects with densities less than this will float.
What causes atmospheric pressure?
The weight of air above a surface
Atmospheric pressure is exerted on everything around us.
What happens to atmospheric pressure as altitude increases?
It decreases
This is due to fewer air molecules and less weight of air above.
