1.1 States of matter Flashcards
States of matter (32 cards)
What are the three main states of matter?
Solids
Liquids
Gases
What are the properties of solids?
Fixed volume
Fixed shape
High density
Does not flow
Particles vibrate in place
Closely packed together
Arranged in a regular pattern
What are the properties of liquids?
Fixed volume
No fixed shape - takes the shape of the container
generally flows easily
Medium density, less dense than solids but more dense than gases
Particles move and slide past each other
Particles are close together but not in a regular pattern
What are the properties of gases?
No fixed shape or volume, takes shape of container
Low density
Particles are far apart
Move quickly in all directions
Flows easily
No regular arrangement
Can be compressed easily
Particles collide with each other and the sides of the container (this is how pressure is created)
What is melting?
Melting is the change of state from a solid to a liquid.
At what temperature does melting occur?
Melting occurs only at a specific temperature called the melting point.
What happens to particles during melting?
Heat energy is absorbed and converted into kinetic energy, causing particles to vibrate faster until they break free from their fixed positions and become a liquid.
Q: What is boiling?
Boiling is the change of state from a liquid to a gas.
At what temperature does boiling occur?
Boiling occurs only at a specific temperature called the boiling point.
What happens to particles during boiling?
Heat energy is absorbed and converted into kinetic energy, allowing particles to move fast enough to overcome the forces holding them together and form gas.
What happens during boiling at the particle level?
Heat is needed to form bubbles of gas below the surface of the liquid.
This allows the liquid to turn into gas and escape from the surface.
What is freezing?
Freezing is the change of state from a liquid to a solid.
It happens when a substance is cooled to its freezing point.
Particles lose kinetic energy, move more slowly, and become fixed in a regular pattern.
What is the reverse of melting, and when does it occur?
Freezing is the reverse of melting. It occurs at the same temperature as the melting point, but energy is released instead of absorbed.
What is evaporation?
Evaporation is the change of state from liquid to gas, occurring only at the surface of the liquid and at temperatures below boiling point.
What happens to particles during evaporation?
The faster particles at the surface gain enough energy to overcome intermolecular forces and escape into the air as gas.
When does evaporation occur?
Evaporation takes place from the surface of the liquid.
Evaporation happens when high-energy particles at the surface of a liquid escape into the air.
It can occur at any temperature, not just the boiling point.
How does surface area affect the rate of evaporation?
The larger the surface area, the faster a liquid evaporates, because more particles are exposed and able to escape.
What is condensation?
Condensation is the change of state from gas to liquid.
What happens to particles during condensation?
Gas particles lose energy, move slower, and come closer together to form a liquid.
Condensation can happen over a range of temperatures, not just at a fixed point.
How does cooling a gas lead to condensation?
When a gas is cooled, its particles lose energy.
As they collide, they no longer have enough energy to bounce apart and instead stick together, forming a liquid.
What is a pure substance?
A pure substance consists of only one substance without any contaminating impurities.
How can we test the purity of a sample?
By checking their melting and boiling points as these values of a pure substance will be precise and predictable.
What is the standard temperature used to determine the state of a substance?
25 degree celsius
What happens to evaporation when temperature rises?
Evaporation is faster
