Unit 1b. Atomic Orbitals & Electronic Configurations

Question 1

29b

Hund’s Rule

Answer 1

degenerate orbitals fill singly to maximise parallel spins

( increase spin multiplicity)

Question 2

What does “degenerate” man in terms of subshell orbitals?

Answer 2

They are equal in energy

Question 3

29c

Pauli Exclusion principle

Answer 3

• 2 electrons in same atom cannot have same 4 quantum numbers
• no orbital can hold more than 2 electrons

Question 4

Principal Quantum Number ( n )

Answer 4

• denotes shell number ( like Nat 5 and Higher)
• higher n = bigger s orbital

Question 5

Angular momentum number ( l )

Answer 5

• denotes the type of subshell within an electron shell.
• can range in values from 0 to (n-1)

Question 6

Magnetic quantum number

Answer 6

• describes the orientation of the orbitals within a subshell.
• range from -l to +l

Question 7

Spin magnetic quantum number (m_s )

Answer 7

• denotes the spin of an electron
• Can be + ½ or - ½

Question 8

What is meant by the f block of the periodic table?

Answer 8

Elements which have their outermost electron in an f-orbital

Question 9

Aufbau principle

Answer 9

states that electron orbitals fill up in order of increasing energy

Question 10

What is meant by the s-block of the periodic table

Answer 10

Elements which have their outermost electron in an s- orbital

Question 11

What is meant by the p block of the periodic table?

Answer 11

Elements which have their outermost electron in a p-orbital.

Question 12

Explain why N has higher 1st ionisation energy than O.

Answer 12

The electron being removed in N is from a stable ( half-full p subshell) electron arrangement

Question 13

Explain why Be has a higher 1st ionisation energy than B

Answer 13

The electron being removed in Be comes from a stable ( full s subshell) e arrangement

Question 14

What is meant by the d block of the periodic table?

Answer 14

Elements which have their outermost electron in a d-orbital