C1

Question 1

What is an atom

Answer 1

The smallest particle of an element - they contain a positive nucleus made of protons and neutrons which is orbited by electrons

1×10^10m

Question 2

What is an element

Answer 2

Substance whose atoms have the same atomic number

Question 3

What is a particle

Answer 3

A tiny piece of matter such as an atom ion or molecule

Question 4

What is a molecule

Answer 4

A particle consisting of two or more non-metals which are covalently bonded

Question 5

What is a proton

Answer 5

A positive particle with a relative mass of 1 and a relative charge of + 1

Question 6

What is a neutron

Answer 6

A neutral particle with a relative mass of 1 and a relative charge of 0

Question 7

What is an electron

Answer 7

A negative particle with a relative mass of 0.0005 and a relative charge of -1

Question 8

What is a chemical symbol

Answer 8

A letter / letters used to represent an element

Question 9

What is an elementd atomic number

Answer 9

The number of protons in the nucleus of an atom
(Which is equal to the number of electrons)

Question 10

What is an elements mass number

Answer 10

Number of protons and neutrons in an atoms nucleus

Question 11

What are isotopes

Answer 11

An atom with a different number of neutrons to its traditional element

Question 12

What is an ion

Answer 12

A charged particle formed when atoms gain or lose electrons

Question 13

Which number is always higher the mass number or atomic number

Answer 13

The mass number as it counts both neutrons and protons

Question 14

What did Democritus and Lecuppis believe

Answer 14

If you could not cut something any futher you where left with an atom - they were indivisible and could not be seen

Question 15

What was John Daltons model of the atom

Answer 15

A tiny solid ball where all atoms in an element are the same and different elements contain their own atoms

Question 16

What was JJ Thomsons model of the atom

Answer 16

He believed an atom was made of negative electrons floating in a positive mass.
He used the plum pudding model to show that the plums (electrons) where embedded in a pudding (positive mass)

He believed the mass may be solid or a cloud

Question 17

What was Ernest Rutherfords model / what did he do

Answer 17

He fired alpha particles at a piece of gold foil
He expected the alpha particles to go through the foil but some came back

To explain this he said that atoms were made of a positive nucleus with negative electrons orbiting it

Question 18

What did Niels Bohr do?

Answer 18

With Thomsons model you would expect the electrons to spiral until they hit the nucleus so Bohr said that:

Electrons can only move in fixed shells - electron shells - around the nucleus

Question 19

What did James Chadwick discover

Answer 19

Neutrons

Question 20

What is a chemical change

Answer 20

A reaction that makes a new substance and is difficult to change

Question 21

What is a physical change

Answer 21

A reversible change where no new substances are made

This change can easily be observed

Question 22

What are the limitations of using the particle model

Answer 22

It doesn’t show

Forces between the particles
The size of particles
The space between the particles

Question 23

What is the particle model

Answer 23

A model showing the states - solid liquid and gas

Particles are represented as hard spheres

Question 24

How are particles held together

Answer 24

Through electrostatic bonds of attraction