Particles up to level 6 Flashcards
Explain what density is
What is the equation for density
Density is the mass per unit volume of a substance. This means it tells us how packed together the particles are
The equation for density is:
How do you calculate the volume of a regular solid and use this to find the density?
To find the volume of a regular solid you need to measure the length, breadth and depth and multiply them together.
Then you find the mass on a set of mass scales and find the density by using the formula density = mass/volume
How do you measure the volume of an irregular solid and use this to find the density of the object?
To find the density of an irregular object you need to use a displacement can. You fill the can with water, drop the object into the water and measure the volume of water that comes out of the can.
You then measure the mass on a mass balance and use the equation density = mass/volume to find the density of the object.
What are the conditions requred for something to float?
For an objet to float it needs to be less dense than the liquid that it is in.
What are the properties of a solid
Fixed shape
Dense
Cannot be compressed
Hard
What are the properties of a liquid?
Can flow
Takes the shape of its container
Dense
Cannot be compressed
What are the properties of a gas?
Can flow
Low density
Takes the shape of its container
Easily compressed
What are the changes of state labelled A-F in this diagram
A = Freezing
B = Melting
C = condensing
D = Evaporating/boiling
E = Deposition
F = Sublimation
How are the particles arranged in a solid?
How do the particles relate to its properties?
The particles in a solid are arranged close together in a regular order and are attached by strong bonds
Solids cannot flow becuase the particles are held together by the bonds between them. It is dense becuase the particles are all touching.
How are the particles arrange in a liquid?
How does the particle arrangement relate to it’s function?
The particles in a liquid are arranged in an irregular pattern but they are still touching. They are held together by weak intermolecular bonds.
Becuase the particles can move past each other, a liquid can flow and take the shape of its container. It is dense and cannot be easily compressed because the particles are close together
How are the particles arranged in a gas?
Explain how the particle arrangment of a gas relates to its properties
The particles in a gas are arranged so that they are randomly placed and are very far apart
A gas can flow becuase the particles can move past each other, this means it also takes the shape of its container. Gasses are not dense because there are spaces between the particles and can be easiliy compressed becuase these spaces can be made smaller
What is internal energy?
|nternal energy is the total energy of the particles of a substance
What is internal kinetic energy?
How do we detect internal kinetic energy?
Internal kinetic energy is the movement energy of the particles in a substance
The internal kinetic energy of a substance determines its temperature. The higher the internal kinetic energy the higher the temperature
What is the internal potential energy of a substance?
How do you change internal potential energy?
Internal potential energy is the energy of the particles becuase of their position and arrangement
Particles have more internal potential energy when they are further apart, or more disorganised. When they change state from solid to liquid (melt) or from liquid to gas (boil/evaporate) they gain internal potential energy. When they change state from gas to liquid (condense) or from liquid to solid (freeze), they loose internal potential energy.
Define the term ‘melting point’
Melting point is the temperature at which a substance changes state between a solid and a liquid. If the temperature is above the melting point it is a liquid, and if the temperature is below the meltion point it is a solid.