Topic 1 - Atomic Structure and the Periodic Table

Question 1

Describe the alpha particle scattering experiment:

Answer 1

1. Scientists fired alpha particles at a thin sheet of gold foil
2. It was expected that the particles would travel right through
3. However, whilst most did, some were deflected off at different angles or directly back
4. This showed that there was a very small, very dense nucleus within the atom which caused the alpha particles to be moved off of their normal path

Question 2

Define an isotope

Answer 2

Atoms of an element which have the same number of protons but different numbers of neutrons

Question 3

What is an element?

Answer 3

Substances that only consist of atoms with the same atomic number

Question 4

How do you calculate the size of an atom by using the size of the nucleus?

Answer 4

Multiply the size of the nucleus by 10,000 .e.g. Nucleus = 20 cm radius
Atom = 200,000 cm radius

Question 5

What is a compound?

Answer 5

A substance formed from two or more different elements in fixed proportions, held together by chemical bonds