1.3: Atomic Theory

Question 1

Atom

Answer 1

The smallest particle of an element that retains the properties of that element.

Question 2

ELectrons

Answer 2

Negatively charged particles surrounding the atomic nucleus

Question 3

Neutron

Answer 3

Uncharged particle in the atomic nucleus, a subatomic particle that has no charge

Question 4

Nucleus

Answer 4

The positively charged centre of an atom, which contains protons and neutrons.

Question 5

Proton

Answer 5

A positively charged particle in the atomic nucleus

Question 6

Subatomic particles

Answer 6

Particles such as protons, neutrons, and electrons that are smaller than atoms

Question 7

Daltons atomic theory

Answer 7

According to dalton: Atoms that make up gold are different from the atoms that make up lead/ different atoms consist of different atoms.

Question 8

J.J Thomson’s atomic theory

Answer 8

He proposed a “raisin bun” model of the atom

Atoms have smaller particles called electrons.

Question 9

Ernest Rutherford’s atomic theory

Answer 9

Ernest Rutherford discovered the nucleus of the atom with his famous gold foil experiment.
Later he also established that there must be a particle with a positive charge, a proton and a particle that had no electric charge a neutron.
Rutherfords Model: Electrons move about a nucleus.

Question 10

Niels Bohr’s Atomic theory

Answer 10

He proposed that electrons surround the nucleus in specific energy “levels” or “shells”. This means that each electron has a particular amount of energy.
More electricity and energy makes the electron jump to a higher energy level.
When the electron releases energy in the form of light, it falls to a lower energy level.
Bohr’s Model: electrons have different energy levels

Question 11

Electric Charge

Answer 11

Electric charge comes in two types: positive and negative
Protons have a positive charge, and electrons have a negative charge.
All atoms have an equal number of protons and electrons. This means that the charges add up to zero making the Atom uncharged or neutral.

Question 12

The Atomic Nucleus

Answer 12

The nucleus always has a positive charge because of the protons and electrons canceling each other out.
Protons and neutrons are held in the center of the nucleus.

Question 13

Electrons

Answer 13

Electrons occupy special regions called energy levels, or shells which surround the nucleus.
The region that electrons occupy accounts for well over 99.99 percent of the volume of an atom.
Each electron occupies one whole energy level at one time.