Chapter 6 - Physics Flashcards
How would you measure the density of a solid object or a liquid?
Measure it’s mass and it’s volume, then use the density equation.
What shape are the particles of a solid held in?
They are held in fixed positions, they are the least energetic of the states of matter.
How do the particles in a liquid move about?
They move about at random and are in contact with each other. They are more energetic than particles in a solid.
How do the particles in a gas move about?
They move about randomly and are far apart (so gases are much less dense than solids and liquids). They are the most energetic of the states of matter.
What happens when a substance changes state?
It’s mass stays the same because the number of particles stays the same.
What is a pure substance’s melting point?
It is the temperature at which it melts (which is the same temperature at which it solidifies)
What is a pure substance’s boiling point?
It is the temperature at which it boils (which is the same temperature at which it solidifies)
What is needed to melt a solid or to boil a liquid?
Energy.
When does boiling occurs?
It occurs throughout a liquid at it’s boiling point.
When does evaporation occur?
It occurs from the surface of a liquid when it’s temperature is below it’s boiling point.
What does the flat section of a temperature-time graph give you?
It gives you the melting point or the boiling point of a substance.
What does increasing the temperature of a substance do?
It increases it’s internal energy.
What does the strength of the forces between the particles of a substance explain?
Why it is a solid, liquid or gas.
What does the pressure of a gas on a surface caused by?
It’s caused by the particles of the gas repeatedly hitting the surface.
What does latent heat mean?
It means the energy needed for a substance to change it’s state without changing it’s temperature.
