Particle model of matter (Seneca) Flashcards
Atoms are very small and have a radius of about …
1 × 10-10 metres.
The electrons are arranged at different distances from the nucleus (————————).
different energy levels
The electrons are arranged at —————————— (different energy levels).
different distances from the nucleus
The radius of a nucleus is less than ————- of the radius of an atom.
1/10 000
Most of the mass of an atom is concentrated in the …
nucleus
Protons have a relative charge of …
+1.
An element’s atomic number is the …
number of protons it possesses.
All atoms of the ——- element have the same number of protons.
same
Electrons have a relative charge of …
-1.
Electrons are found in …
fixed orbits around the nucleus.
Neutrons have a relative charge of …
0
Ernest Rutherford discovered the nucleus by …
firing a beam of alpha particles at thin metal foils (only a few atoms wide).
Why would the alpha particles be deflected by a smaller angle if the thin metal foil was made of a lighter element?
The nuclei of lighter elements contain fewer protons. This means they have a lower charge. Each alpha particle will, therefore, experience a smaller electric force acting on it and so deflect by a smaller angle.
Each electron shell has a different ———- level.
energy
Electrons (negatively charged particles) have been shown to orbit the nucleus at ——— distances.
fixed
When an atom absorbs or emits electromagnetic radiation, its ————— can change.
electron arrangements
When atoms emit electromagnetic radiation, electrons move to a —————- the nucleus.
lower energy level, closer to
When atoms absorb electromagnetic radiation, electrons move to a ——————— the nucleus.
higher energy level further away from
When atoms ——- electromagnetic radiation, electrons move to a higher energy level further away from the nucleus.
absorb
When atoms ———-electromagnetic radiation, electrons can drop to a lower energy level, closer to the nucleus.
emit
What can be emitted by atoms to change the electron arrangement in an atom?
Radiation
Density (g/cm3) =
Mass(g) /volume (cm3)
The Law of Displacement says that …
an object completely submerged in a fluid (like water) will replace an amount of fluid equal to its own volume.
An object floats in a fluid if the density of the object is ——— than the density of the fluid.
lower
The force that keeps the object afloat is called …
upthrust.
Solids are the ——- state of matter.
densest
Solids particles are —————— together.
packed tightly
Gases are the ——— dense state of matter.
least
The particles are ———— with negligible (tiny) forces between particles.
free to move
The particles are free to move with —————- forces between particles.
negligible (tiny)
Liquids are 1. dense than solids but 2. than gases.
- less
- denser
The particles in liquids can move …
around each other.
What type of change is a change of state?
Physical
Density (kg/m3) =
Mass (kg)/volume (m3)
The energy in an object’s kinetic store comes from the …
random motion of its particles.
The temperature of a body (object) is a measure of the …
energy in the kinetic stores of its particles.
Increasing a body’s temperature increases the energy in the …
kinetic stores of the body’s particles
Increasing a body’s temperature increases the energy in the kinetic stores of the body’s particles, which means that the energy in the ————- also increases.
body’s internal store
The energy in an object’s potential store comes from the …
potential energy stored in the bonds between particles.
Which type of energy store comes from the energy stored in the bonds between particles?
Potential energy store
change in internal energy (j) =
mass (kg) specific heat capacity ( J/kg°C x temperature change (C)
The amount of energy in an object’s internal store is the …
sum (total) of the kinetic and chemical potential stores of the object’s particles.
The energy in an object’s kinetic store comes from the …
random motion of its particles.
The temperature of a body (object) is a measure of …
the energy in the kinetic stores of its particles.
Increasing a body’s temperature increases the energy in the kinetic stores of the body’s particles, which means that the energy in the body’s internal store …
also increases.
The energy in an object’s potential store comes from the …
potential energy stored in the bonds between particles.
change in internal energy (J) =
mass (Kg) × specific heat capacity (J/kg°C) ×temperature change(C)
The specific heat capacity of a substance is the amount of energy needed to …
increase the temperature of 1 kg of that substance by 1°C.
Specific heat capacity (J/kg°C)=
change in internal energy (J) /mass (Kg) x maximum temperature rise (C)
thermal capacity=
mass×specific heat capacity
Leslie’s cube is a …
metal box with 4 different colour sides (black, matte black, white, unpainted).
If you pour hot water into the Leslie cube, the ———- side will emit more infra-red radiation than the other sides.
matte (dull) black
If you pour hot water into the Leslie cube, the matte (dull) black side will …
emit more infra-red radiation than the other sides.
The ————— emitted from the Leslie cube is measured using a thermopile (a sensitive thermometer).
infra-red radiation
What experiment can we use to measure the effectiveness of different materials as thermal insulators?
Leslie’s sphere
During the Leslie’s cube experiment, measure the temperature of the body (object) at …
the start and measure the maximum temperature of the body at the end.
During the Leslie’s cube experiment, a joulemeter is used to
measures the energy supplied by the heater
During the Leslie’s cube experiment, the heater increases the …
internal energy of the body.
Explain how Leslie’s cube works.
- Leslie’s cube is a metal box with 4 different colour sides (black, matte black, white, unpainted).
- If you pour hot water into the cube, the matt (dull) black side will emit more infra-red radiation than the other sides, because dull black surfaces are the best emitters of heat.
- The infra-red radiation emitted is measured using a thermopile (a sensitive thermometer).
For the same material, its boiling point is the same as its
condensing point.
When the temperature of a gas decreases to the boiling point, the strength of the forces between particles …
increases and the particles condense to become a liquid
When the temperature of a liquid decreases to the melting point, the strength of the forces between particles …
increases and the liquid solidifies to become a solid.
For the same material, its melting point is the same as its …
freezing point.
Melting is sometimes also called…
fusion.
If we heat a solid, the solid particles vibrate —–energetically, until they have enough energy to overcome the forces between them.
more
If we heat a solid, the solid particles vibrate more energetically, until …
they have enough energy to overcome the forces between them.
If we heat a liquid, the liquid particles move —– energetically until they have enough energy to escape completely from the forces between them.
more
If we heat a liquid, the liquid particles move more energetically until …
they have enough energy to escape completely from the forces between them.
The particles become a gas and move …
completely freely.
The temperature needed for this to happen is the boiling point. Boiling can be called …
vaporisation.
When the temperature of a liquid decreases to the melting point, the strength of the forces between particles …
increases and the liquid solidifies to become a solid.
If we heat a solid, the solid particles vibrate more energetically, until ———————. This is when the solid melts (becomes a liquid).
they have enough energy to overcome the forces between them
When the temperature of a gas decreases to the boiling point, the strength of the forces between particles …
increases and the particles condense to become a liquid.
Boiling - liquid to gas
If we heat a liquid, the liquid particles move more energetically until ————————. The particles become a gas and move completely freely.
they have enough energy to escape completely from the forces between them
Specific latent heat is the latent heat per 1kg of mass.
It is a way to …
standardise across objects that have different masses.
If we measure energy using the change in temperature, this energy transfer will …
The energy is transferred without the temperature changing.
not be measured.
If we measure energy using the change in temperature, this energy transfer will not be measured.
The energy is transferred without …
the temperature changing.
When a solid becomes a liquid or a liquid becomes a solid, this hidden energy is called the …
latent heat of fusion.
When a gas becomes a liquid, or a liquid becomes a gas, this hidden energy is called the …
latent heat of vaporisation.
When a substance changes state, this energy is absorbed (used) to ————–, rather than transfer kinetic energy to a substance’s particles.
create or weaken bonds
When the substance changes state (melting or boiling), energy is …
absorbed without changing the substance’s temperature.
What is the energy that is transferred to a substance without the substance’s temperature changing called?
Latent heat
The energy (taken in or given out in a change of state) is equal to the …
mass multiplied by the specific latent heat.
What are the units of latent heat of vapourisation?
J/kg
Energy given out or absorbed in a state-change is given by the …
product of the mass of the substance and the latent heat of vaporisation/fusion.
Terms beginning with specific are ————— . It is a way of standardising measurement so that we can test objects of different weights and sizes.
measured per kilogram
Terms beginning with specific are measured per kilogram. It is a way of …
standardising measurement so that we can test objects of different weights and sizes.
How can you detect latent heat?
Use a joulemeter and measuring the energy supplied to change state.
Energy for a change of state (J) =
mass (kg) x specific latent heat (J/kg)
mass (kg) x specific latent heat (J/kg) =
Energy for a change of state (J)
Describe the experiment for the Specific Latent Heat of Fusion.
- To determine water’s specific latent heat of fusion we use the equation:
specific latent heat = energy change ÷ mass. - Gently heat ice in a funnel until it melts. Then measure the mass of the melted ice (water in the beaker).
- Measure the amount of energy supplied by the heater using a joulemeter (this gives us the energy change).
- Calculate the specific latent heat of fusion using our equation above.
The latent heat of fusion (melting) of water/ice can be measured using a …
joulemeter.
Describe the experiment for the Specific Latent Heat of Vapourisation.
- To determine water’s specific latent heat of vapourisation we use the equation:
specific latent heat = energy change ÷ change in mass.
Measure the mass of water in a beaker. - Boil some water and then measure the mass of the water again.
- Mass at the start - mass at the end = change in mass.
- Measure the amount of energy supplied by the heater using a joulemeter (this gives us the energy change).
- Calculate the latent heat of vapourisation using our equation above.
Gases can be compressed because …
their particles are very far apart.
When water evaporates to become steam (gas), its volume increases by …
1000x.
The particles in a gas are free to move in any direction. Because of this, a gas can …
flow, has no fixed shape and completely fills its container.
The particles in a gas move …
randomly and are not organised in any way.
Liquids cannot be compressed because …
their particles are already very close together.
In a liquid, the particles are in contact with one another, but they can still move. This allows a liquid to …
flow and take the shape of its container.
Particles in a liquid are arranged in a …
disordered pattern.
A solid has a ———– because of the strong forces between its particles.
fixed shape
A solid has a fixed shape because of the …
strong forces between its particles.
Solids cannot be compressed because …
their particles are already very close together and cannot flow.
The particles in a solid are arranged in …
an ordered pattern.
The particles in a solid …
vibrate in a fixed point.
A gas exerts ——– on the walls of its container.
pressure
There are lots of gas particles ——– with the container each second.
colliding
When a gas particle collides with the wall of its container, its …
momentum changes and it bounces back off the wall.
When a gas particle collides with the wall of its container, its momentum changes and it bounces back off the wall.
This exerts a force on …
both the particle and the wall.
The pressure exerted on the wall is equal to …
the force (of the ball) per unit area (of the wall being hit).
The higher the temperature of a gas, the higher the …
kinetic energy stored in the gas’ particles.
As you heat a gas, you transfer more kinetic energy to the gas’ particles.
This increases the …
speed of the particles.
As you heat a gas, you transfer more ———- to the gas’ particles.
This increases the speed of the particles.
kinetic energy
The ———————— to the force multiplied by time. It is also the same as impulse.
change in momentum is equal
The change in momentum is equal to the ———– multiplied by time. It is also the same as impulse.
force
The change in momentum is equal to the force multiplied by time. It is also the same as ———–.
impulse
The change in momentum is equal to the force multiplied by ——-. It is also the same as impulse.
time
Change in momentum =
force (N) x time (s)
The pressure of a gas produces a net force (the sum of all the forces) at ———- to the wall of a container.
right angles
An increase in temperature leads to a …
higher kinetic energy of particles.
An increase in temperature leads to a higher kinetic energy of particles.
These particles collide with (hit) the walls of the container with …
more force.
An increase in temperature leads to a higher kinetic energy of particles.
These particles collide with (hit) the walls of the container with more force.
The container will …
This is because the gas pushes it outwards.
expand (increase its volume) if it is able to.
An increase in temperature leads to a higher kinetic energy of particles.
These particles collide with (hit) the walls of the container with more force.
The container will expand (increase its volume) if it is able to.
This is because the gas …
pushes it outwards.
If we increase the temperature of the gas in a fixed volume, then the particles will …
collide with (hit) the container walls with more force.
If we increase the temperature of the gas in a fixed volume, then the particles will collide with (hit) the container walls with more force.
Therefore …
the pressure will increase.
Doing —– on a gas increases the gas’ internal energy.
work
Which type of energy is increased by increasing the temperature of gas particles?
kinetic energy
What two stores of energy are added together to calculate the internal store?
- kinetic energy
- potential energy
What is the average room temperature?
20 C
P × t =
E
In what environment would the relative mass of an atom change?
mass is constant across all environments
