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Question 1

What was Dalton’s model of the atom?

Answer 1

Dalton’s model of the atom was a small, indestructible sphere.

Question 2

How did Thomson discover the electron?

Answer 2

Thomson discovered the electron through cathode rays, and how they have particles that have less than one-thousandth the mass of an atom

Question 3

What is Thomson’s model of the atom?

Answer 3

Thomson made the plum-pudding model. In this model, the atom consists of negative electrons embedded in a positive mass.

Question 4

What did Rutherford do and what happened in his experiment?

Answer 4

Rutherford, along with Geiger and Marsden, shot alpha particles at a piece of thin gold foil. In this, many particles went through, but some deflected their path, and some even came straight back

Question 5

How did Rutherford explain his results?

Answer 5

To explain his results, Rutherford said that an atom is made of a tiny positively charged nucleus with electrons orbiting it

Question 6

What is the Bohr model of the atom?

Answer 6

Bohr suggested that electrons can only move in fixed orbits, called electron shells, around the nucleus.

Question 7

What is the typical size of atoms and small molecules?

Answer 7

10^-10m, which is an order of magnitude

Question 8

How does the temperature affect gas pressure for a container that cannot expand?

Answer 8

As the temperature increases, the gas particles collide more frequently with the sides of the container, which produces a bigger pressure.

Question 9

Draw a graph to show how gas’ pressure and volume varies with temperature

Answer 9

see p.g. 35

Question 10

What is density?

Answer 10

Density tells you how much mass there is is a certain volume

Question 11

What is the equation to calculate density where mass is conserved?

Answer 11

density (kg/m3) = mass (kg) / volume (m3)

Question 12

What are the differences in density between different states of matter?

Answer 12

A substance in the solid state in denser than the same substance as a liquid or gas because there are more particles in that substance

Question 13

How is mass conserved when substances melt, freeze, evaporate, condense or sublime?

Answer 13

As particles do not appear or disappear during the changes of state.

Question 14

What are the differences between physical and chemical changes?

Answer 14

In a physical change, you do not make new substances. The material recovers its original properties if the change is reversed. In a chemical change, you cannot easily reverse it, because new substances form.

Question 15

How will heating a system change the energy stored within the system?

Answer 15

It can raise its temperature as the kinetic energy of the particles increase.
It can produce a change of state
It can make chemical reactions happen

Question 16

What is specific heat capacity?

Answer 16

Specific heat capacity is the energy needed to raise the temperature of 1kg of a substance by 1K. It is measured in J/kg K

Question 17

How do you calculate with specific heat capacity?

Answer 17

By using the following equation:

change in thermal energy (J) = mass (kg) x specific heat capacity (J/kg K) x change in temperature (K)

Question 18

What is specific latent heat of fusion?

Answer 18

Specific latent heat of fusion is the energy transferred when 1kg of a substance changes from solid state to liquid state or vice versa

Question 19

What is specific latent heat of vaporisation?

Answer 19

Specific latent heat of vaporisation is the energy transferred when 1kg of a substance changes from liquid state to gas state or vice versa

Question 20

How do you calculate with specific latent heat?

Answer 20

You use the equation:

thermal energy in a change of state (J) = mass (kg) x specific latent heat (J/kg)

Question 21

How is specific heat capacity different from specific latent heat?

Answer 21

Both involve energy changes for 1kg of a substance, but:
Specific heat capacity is about change in temperature
Specific latent heat is about change in state