Chapter 1: Atomic Structure

Question 1

What are the charges of protons, neutrons, and electrons?

Answer 1

Protons: +1
Neutrons: 0
Electrons: -1

Question 2

What is the atomic number?

Answer 2

Number of protons in an atom.

Question 3

What is the mass number?

Answer 3

Protons + Neutrons in an atom.

Question 4

How does atomic radius change across a period and down a group?

Answer 4

Across: decreases
Down: increases

Question 5

What defines an isotope?

Answer 5

Same protons, different neutrons.

Question 6

How do isotopes differ in physical properties?

Answer 6

Different masses and densities.

Question 7

Orbitals and electrons in s, p, d sub-shells?

Answer 7

s sublevel: 1 orbital, max 2 electrons
p sublevel: 3 orbitals, max 6 electrons
d sublevel: 5 orbitals, max 10 electrons

Question 8

Order of energy levels?

Answer 8

1s < 2s < 2p < 3s < 3p < 4s < 3d < 4p

Question 9

Shorthand configuration for Fe?

Answer 9

[Ar] 4s^2 3d^6

Question 10

What is ionisation energy (IE)?

Answer 10

Energy to remove 1 mole of electrons.

Question 11

Trends in ionisation energy?

Answer 11

Across a period: increases; Down a group: decreases

Question 12

What does a large jump in ionisation energies indicate?

Answer 12

Electron removed from a new shell.

Question 13

Factors affecting ionisation energy?

Answer 13

Nuclear charge, radius, shielding, repulsion.

Question 14

How does ionisation energy data reveal electronic configuration?

Answer 14

Shows number of electrons per shell.

Question 15

How can ionisation energy data identify an element’s position?

Answer 15

By comparing trends with known elements.