Particle Theory (3)

Question 1

What is density

Answer 1

The measure of how compact a substance is

Question 2

What is the unit for density

Answer 2

(kg/m cubed )

Question 3

Describe solids

Answer 3

particles are tightly packed in a regular structure

Question 4

Describe a liquid

Answer 4

particles are tightly packed but free to move past each other

Question 5

Describe a gas

Answer 5

particles are spread out and move randomly

Question 6

How would you measure the density of a solid object (regular object)

Answer 6

1) Use a ruler to measure the length (l), width (w) and height (h) of a steel cube.
2) Place the steel cube on the top pan balance and measure its mass.
3) Calculate the volume of the cube using (l × w × h).
4) Use the measurements to calculate the density of the metal.
5) Use vernier callipers to measure the diameter of the sphere.
6) Place the metal sphere on the top pan balance and measure its mass.
7) Calculate the volume of the sphere
8) Use the measurements to calculate the density of the metal.

Question 7

How would you measure the density of a solid object (irregular object)

Answer 7

1) Place the stone on the top pan balance and measure its mass.
2) Fill the displacement can until the water is level with the bottom of the pipe.
3) Place a measuring cylinder under the pipe ready to collect the displaced water.
4) Carefully drop the stone into the can and wait until no more water runs into the cylinder.
6) Measure the volume of the displaced water.
7) Use the measurements to calculate the density of the stone.

Question 8

How would you measure the density of any liquid

Answer 8

1) Place the measuring cylinder on the top pan balance and measure its mass.
2) Pour 50 cm3 of water into the measuring cylinder and measure its new mass.
3) Subtract the mass in step 1 from the mass in step 2. This is the mass of 50 cm3 of water.
4) Use the measurements to calculate the density of the water.

Question 9

What is internal energy

Answer 9

the total amount of kinetic energy and potential energy of all the particles in the system.

Question 10

What is The conservation of energy

Answer 10

• means that, assuming no energy is lost to the environment, any energy transferred to a material will be distributed between the chemical store and the thermal store of the internal energy.

Question 11

What is temperature

Answer 11

a measure of the average speed of the particles. This is based on the kinetic energy of individual particles.

Question 12

What is the specific latent heat

Answer 12

Specific latent heat is the amount of energy required to change the state of 1 kilogram (kg) of a material without changing its temperature.