PARTICLE MODEL OF MATTER (ORIGINAL)

not edited to only have the stuff we need for eoys

What is density?

the mass per unit volume (1m^3 or 1cm^3) of a substance

Equation for density?

mass/volume (m/v)

Equation for volume?

weight x length x height

How to calculate the density of a cuboid

1. measure weight, height and length

2. calculate the volume

3. find the mass of the object using a weighing scale

4. calculate the density

How to calculate the density of a liquid

1. weigh the measuring cylinder on a weighing scale

2. use a measuring cylinder to find the volume of a liquid

3. using a weighing scale calculate the mass

4. subtract the mass presented by the weighing scale by the mass of the measuring cylinder to get the mass of the liquid

5. calculate the density using volume / mass

How do you calculate the mass of the liquid using a weighing scale?

the empty container - the container with the liquid

How to calculate the density of an irregular solid

1. measure the mass of the object using a weighing scale

2. fill the displacement can until the water is level with the bottom of the pipe

3. place a measuring cylinder under the pipe

4. submerge the shape in the can and wait until no more water runs out

5. measure the volume of the displaced water using the measuring cylinder

6. calculate the density

Describe a solid particle diagram / solid particle arrangement

• particles are in a regular fixed pattern

• particles vibrate on the spot

• particles are very close together

• very strong forces/bonds

liquid particle diagram

• particles are in a random pattern

• particles slide

• particles are close together

• weak forces/bonds

gas particle diagram

• particles have no pattern

• particles move freely and in random directions

• particles are far apart

• negligible forces/bonds

What does negligible mean?

too small to be significant

Special properties of a solid?

• densest

• keeps it shape

• particles vibrate faster when hotter

• can't be compressed

Special properties of a liquid?

• relatively dense

• can flow

• can't be compressed

Special properties of a gas?

• least dense

• can be compressed

What are the changes of state?

sublimation, deposition, melting, freezing, evaporation, condensation

What is sublimation?

solid to gas

What is deposition?

gas to solid

What is melting?

solid to liquid

What is freezing or solidifying?

liquid to solid

What is condensation

gas to liquid

What is evaporation or boiling?

liquid to gas

Difference between evaporation and boiling?

boiling is when a liquid becomes a gas at the boiling point and evaporation is when a liquid becomes a gas below the boiling point with only the surface particles changing shape

Describe the cooling stearic acid experiment

• clamp the test tube of stearic acid

• record the temperature every 2 minutes

What should we not do in a cooling stearic acid experiment?

• don’t clamp too tightly otherwise the test tube will break

• do not move the thermometer once in the stearic acid so it will be a more accurate reading

What happens to the particles during the stearic acid experiment

they organise into neat rows

What is internal energy?

energy stored by the particles that make up the system

Equation for internal energy?

sum of kinetic energy of particles + sum of the potential energy of the particles (the sum of all the energy in the particles)

What is potential energy?

the energy stored in the bonds/intermolecular forces when changing state (the energy of their bonds and arragngement)

What is kinetic energy?

energy of the particles motion

When does the kinetic energy of the particles change?

when the temperature changes

How to calculate your pressure on the ground?

• draw the outline of your shoe and calculate the area of the sole

• use the scale to measure your weight in Newtons

• calculate the pressure

Equation for pressure?

force/area (f/a)

What is pressure?

the amount of force applied on a unit area (1m^2 or 1cm^2)

What is the correlation between area and pressure?

the smaller the area the larger the pressure

What is the correlation between force and pressure?

the larger the force the greater the pressure

how to increase pressure of a gas

• pump in more gas

• decrease the space

• increase the temperature

what happens to the energy and particles in a temperature time graph when it's a solid, liquid, gas (section a, c, e)

• kinetic energy increases/decreases

• the energy makes the particles move faster

• internal energy increases/decreases

• the particles move slightly apart

what happens to the energy and particles in a temperature time graph when it's changing state (section b, d)

• potential energy increase/decrease

• the energy is used to break the bonds/forces between particles

• internal energy increases/decreases

• the particles move slightly apart

what happens to the substance/temperature in a temperature time graph when it's a solid, liquid, gas (section a, c, e)

the temperature changes rises/decreases until the boiling or melting point and the state is either solid liquid or gas

what happens to the substance/temperature in a temperature time graph when its changing state (sections b, d)

the temperature is steady and the state changes

What is the resolution in physics?

the smallest increment on an equipment

Example of resolution in physics?

1cm on a ruler

What is meniscus?

the bottom point in the curved upper surface of a liquid in a container

What is a parallax error?

when the volume of a liquid is read when the eye level is above or below the meniscus. It leads to inaccurate volumes being determined