Electrons in Atoms - Electronic Configuration

Question 1

principle energy levels (n)

Answer 1

• each energy level can only hold so many electrons

- maximum number of electrons = 2n^2

Question 2

sublevels

Answer 2

• each level is made of sublevels
• named s, p, d, f, …
• # of sublevels = n
• principal quantum number = n
• 1(n), 1(# of sublevels), s (orbital type) (1)
• 2(n), 2(# of sublevels), s, p (orbital type) (3)
• 3(n), 3(# of sublevels), s, p, d (orbital type) (5)
• 4(n), 4 (# of sublevels), s, p, d, f (orbital type) (7)
• can only hold so many electrons
• the periodic table shows this

Question 3

orbitals

Answer 3

• each sublevel contains orbitals which can hold a maximum of two electrons

Question 4

aufbau principle (build-up)

Answer 4

• lower energy sublevels a re completely filled before electrons enter higher-energy sublevels
• depict using boxes for orbitals and arrows for electrons

Question 5

pauli exclusion principle

Answer 5

• is the quantum mechanical principle which states that two or more identical fermions (particles with half-integer spin) cannot occupy the same quantum state within a quantum system simultaneously.

Question 6

electron configuration notation

Answer 6

• hydrogen 1s^1
• helium 1s^2
• flourine 1s^2 2s^2 2p^5
• phsophorus 1s^2 2s^2 2p^6 3s^2 3p^2

Question 7

noble gas configuration

Answer 7

• symbols for noble gas element in brackets [X] denotes that shells are filled through that element