Y8 Test On 5th December Flashcards
Name the four states of matter
Solid, liquid, gas, plasma
Name the processes of change for physical changes
Condensation Freezing Melting Sublimation Evaporation
Describe the particle arrangement in a solid
The particles are tightly packed so they cannot move, but they can vibrate. They are in an even pattern
Describe the particle arrangement in a liquid
The bonds between particles are weaker, which allows them to slip past each other. There is no regular pattern
Describe the particle arrangement in a gas
In a gas, particles spread out to fill the space they are in, because they can move freely. They can move in any direction at a very high speed
What happens to particles during a change of state?
The amount of energy between each particle changes, causing them to either vibrate more or less
Name some of the properties of metals
Some are soluble. All are solid at room temperature except mercury Some are malleable They are good conductors of electricity They are good conductors of heat
What is strength?
The ability to withstand a force
What is hardness?
The measure of how easy it is to scratch a solid
What is an alloy and why do we make them?
Alloys are a combination of two or more metals. We make them to bring out the best qualities in a solid e.g hardness or shine
What is viscosity?
The ability to flow
What is solubility?
If a mass can dissolve in a solvent
What can make particles move faster?
Heat energy
When air is heated, it becomes…?
Lighter
If air is less dense than other air, it…?
Floats
Why does expansion happen?
When heat causes the particles to vibrate more, which causes more collisions, which causes the space between particles to expand. THE PARTICLES STAY THE SAME SIZE
What is concentration?
A measure of the solute particles in a solvent. If the number is high, the substance is concentrated. If it is low, it is dilute
How would you increase the concentration of a solution?
You would add more solute, or take away some of the solvent
What is pressure?
A measure of the average force of collisions when gas or liquid particles move, and collide with the area of the container’s sides. The pressure is measured in kilopascals (kPa)
What is the difference between higher and lower pressure?
In a high pressure, there are much more collisions with the side of the container because there are more particles
