Science module #13

Model

A schematic description of a system that accounts for its known properties

Nucleus

The center of an atom containing the protons and neutrons

Atomic Number

The number of protons in an atom

Mass Number

The sum of the neutrons and protons in the nucleus of an atom

Isotopes

Atoms with the same number of protons, but different number of neutrons

Element

A collection of atoms that all have the same number of protons

Radioactive isotope

An atom with an unstable nucleus

Half-life

The time it takes for half of the original sample of a radioactive isotope to decay

What are the three constituent parts of the atom in terms of their mass from least massive to most massive

Electron proton neutron

What force keeps the protons and neutrons in the nucleus? what causes this force?

Nuclear force, pions

What force keeps electrons orbiting around the nucleus

electromagnetic force

What is an atom mostly made of?

Empty space

Bohr Orbit 1

2 electrons

Bohr Orbit 2

8 electrons

Bohr Orbit 2

8 electrons

Bohr orbit 3

18 electrons

Bohr orbit 4

32 electrons

Bohr orbit 5

50 electrons