11. P6 Molecules and Matter Flashcards
Explain why object such as ice and wood float when placed in water.
Ice and wood are less dense than water.
What is the definition of the “density” of an object?
It is the mass per unit volume of an object.
The state of matter where the particles are linked by strong forces. They are packed closely together and move very little. The particles usually form a regular and specific pattern.
Solid
The state of matter where the particles have weaker bonds. They are still tightly packed but may move around each other.
Liquid
The state of matter where particles are far apart and are in constant random motion. There is no interactive between the particles.
Gas
The temperature at which a solid turns into a liquid .
Melting Point
The temperature at which a liquid turns into a gas.
Boiling Point
Nome of process when a solid changes to a liquid.
Melting
Name of process when a liquid changes a gas at the boiling point
Boiling
Name of process when a liquid changes to a gas below the boiling point.
Evaporating
Name of process when a gas changes to a liquid.
Condensing
The name given to the sum of the energy of the particles of a substance due to their individual motions and positions.
Internal Energy
Property of a substance which is the amount of energy required to raise the temperature of one kilogram of a substance by one degree Celsius.
Specific Heat Capacity
Often represented by the symbol ‘c’.
Specific Heat Capacity
Units of specific heat capacity.
J/kg°C.
The amount of energy required to change the state of one kilogram of the substance with no change in temperature.
Specific Latent Heat
Often represented by ‘L’.
Specific Latent Heat
Units of specific latent heat.
J/kgC
When molecules collide with the wall of their container they exert a force on the wall. The total force exerted by all of the molecules inside the container on a unit of area of the wall is called?
Gas pressure
What is the amount of space that a substance or object occupies?
Volume
What is the unit of volume?
Metres cubed (m³)
What is the mass per unit volume of a material?
Density
What is the standard unit of density?
kg/m³
When a solid changes into a gas when it is heated without becoming a liquid first.
Sublimation
The amount of energy required to change one kilogram of a solid into a liquid with no change of temperature.
Specific Latent Heat Of Fusion
The amount of energy required to change one kilogram of a liquid into a gas (vapour) with no change of temperature.
Specific Latent Heat Of Vaporisation
What is meant by the random motion of a gas molecule?
Particles moving with a range of different speeds in random directions.
What observations made which provided evidence for the random motion of a gas molecule?
Brownian motion of smoke particles.
Explain how the haphazard and unpredictable motion of smoke particles under a microscope were explained?
Air molecules moving randomly collided with the smoke particles. Providing them with random forces, causing the unpredictable motion.
The unit of pressure.
Pascals (Pa)
Equation linking energy transferred and the specific heat capacity?
E = m x c x ?
Equation linking energy transferred and the specific latent heat?
E = m x L
Equation linking density, volume and mass of an object?
density = mass/volume
What happens to the pressure of a gas in a sealed container when the temperature is increased?
Pressure increases with the temperature of a sealed container of gas.
Explain why the temperature of a sealed container of gas affects the pressure of the gas.
As the temperature increases, the speed increases. Therefore the molecule collide with a greater force and more of them collide with the surface per second.
How do you calculate the volume of a cuboid?
..
How do you calculate the volume of a sphere?
..
What state has particles which are least energetic?
Solid
What state has particles which are most energetic?
Gas
Describe the two difference between boiling and evaporation of a liquid?
Boiling occurs at the liquids boiling point, evaporation at a temperature below this point. Boiling occurs from throughout a liquid, evaporation occurs at the surface.
