Atomic theory

Question 1

What is an atom?

Answer 1

Smallest form of element that carries its properties

Atoms are the fundamental building blocks of matter.

Question 2

What are subatomic particles?

Answer 2

What an atom is composed of

Subatomic particles include protons, neutrons, and electrons.

Question 3

What is a proton?

Answer 3

+ve SAP with 1 amu

Protons are positively charged particles found in the nucleus of an atom.

Question 4

What is an electron?

Answer 4

-ve SAP with negligible mass

Electrons are negatively charged particles that orbit the nucleus of an atom.

Question 5

What is a neutron?

Answer 5

0 charge SAP with 1 amu

Neutrons are neutral particles found in the nucleus of an atom.

Question 6

What is mass number?

Answer 6

Total mass of atom | no. protons + no. neutrons (larger no. in PT)

Mass number represents the total number of protons and neutrons in an atom.

Question 7

What is atomic number?

Answer 7

Total no. of protons (smaller no. in PT)

Atomic number defines the identity of an element and its position in the periodic table.

Question 8

What happens when an atom loses electrons?

Answer 8

Atom has P > e- so it’s positively charged (X+)

This process is known as ionization, resulting in a cation.

Question 9

What happens when an atom gains electrons?

Answer 9

Atom has P < e- so it’s negatively charged (X-)

This process results in an anion.

Question 10

What is the electronic configuration of the first shell?

Answer 10

2 e-

The first shell can hold a maximum of 2 electrons.

Question 11

What is the electronic configuration of subsequent shells?

Answer 11

8 e-/shell

Each shell after the first can hold up to 8 electrons.