S4.1.2 Glossary

Question 1

Atomic model

Answer 1

A representation of the structure of the atom

Question 2

Alpha particle

Answer 2

A particle made of 2 protons and 2 neutrons

Question 3

Atomic number

Answer 3

The number of protons in an atom

Question 4

Dalton’s atoms

Answer 4

Solid spheres which cannot be divided into smaller parts

Question 5

Electron

Answer 5

A very small, negatively charged particle within an atom

Question 6

Electronic structure

Answer 6

A representation of the number of electrons in each energy level

Question 7

Energy level

Answer 7

Also known as shells, the orbit of an electron around a nucleus

Question 8

Isotope

Answer 8

Atoms with the same atomic number but different mass number

Question 9

Mass number

Answer 9

The number of protons and neutrons in an atom

Question 10

Neutron

Answer 10

A neutral particle within an atom with a mass of one

Question 11

Nuclear atom

Answer 11

A model of the atom containing a nucleus at its centre

Question 12

Nuclei

Answer 12

The plural for nucleus

Question 13

Nucleus

Answer 13

The centre of an atom which contains protons and neutrons

Question 14

Plum pudding model

Answer 14

A ball of positive charge with negative electrons embedded in it

Question 15

Proton

Answer 15

A positive particle within an atom with a mass of one

Question 16

Radius

Answer 16

The distance from the outer edge of a circle or sphere to its centre

Question 17

Relative charge

Answer 17

The charge of one particle compared to another

Question 18

Relative mass

Answer 18

Mass of an element, taking into account the proportions of its isotopes

Question 19

Subatomic particle

Answer 19

A small particle found within atoms, e.g. electrons, protons, neutrons