atomic orbitals and electron configurations 1.2

Question 1

subshells

Answer 1

when emission spectra contain double or triple lines it suggests that the electron shells contain subshells which have different energies and shapes

Question 2

how many electrons can each orbital hold

Answer 2

2

Question 3

s orbitals

Answer 3

• spherical
• n = electron shell number
• as n decreases the diameter of the s orbital increases

Question 4

p orbitals

Answer 4

• dumb bell shaped
• there are three orbitals so they hold 6 electrons
• each orbital is of equal energy (degenerate)

Question 5

d orbitals

Answer 5

• they gave 5 d orbitals
• they can hold a total of 10 electrons

Question 6

heisenbergs uncertainty principle

Answer 6

“it is impossible to determine the exact position and momentum of an electron”

Question 7

the 4 quantum numbers

Answer 7

n , l , Ml , Ms

Question 8

quantum number n

Answer 8

• principle quantum number
• tells you the electron shell number
• the higher n is the higher the potential energy
• n is a wave number starting from 1

Question 9

quantum number l

Answer 9

• angular momentum quantum number
• describes the shape of an orbital within a subshell
• it has a value from 0 to (n-1)

Question 10

quantum number Ml

Answer 10

• magnetic quantum number
• tells us what direction the orbitals have (x, y etc)
• have values -l to +l

Question 11

quantum number Ms

Answer 11

• spin quantum number
• an electron behaves as if it has spin
• s can be +1/2 or -1/2
• shown with up or down arrows
• if there are 2 in an orbital they must have opposite spins

Question 12

pauli exclusion principle

Answer 12

no two electrons in any one atom can have the same set of quantum numbers and each orbital holds a maximum of two electrons with opposing spins

Question 13

hunds rule

Answer 13

“when degenerate orbitals are available electrons fill the orbitals singly keeping spins parallel before pairing occurs”

Question 14

degenerate

Answer 14

same energy

Question 15

aufbau principal

Answer 15

orbitals are filled in order of increasing energy and all orbitals within a subshell are degenerate

Question 16

why do electrons fill the 4s orbital before the 3d orbital

Answer 16

because the 4s orbital has a low energy

Question 17

the two exceptions in spectroscopic notation

Answer 17

copper and chromium

Question 18

chromium spectroscopic notation

Answer 18

1s2 2s2 2p6 3s2 3p6 4s1 3d5

Question 19

copper spectroscopic notation

Answer 19

1s2 2s2 2p6 3s2 3p6 4s1 3d10

Question 20

why are copper and chromium exceptions

Answer 20

due to the increased stability that a full or half full shell gives

Question 21

when do elements have a higher ionisation energy than expected

Answer 21

because the electrons are being removed from a complete orbital

Question 22

are complete or incomplete orbitals more stable

Answer 22

complete and half full are more stable than incomplete

Question 23

lone pairs

Answer 23

not all pairs or electrons are involved in bonding and these lone pairs affect the bond angle and shape

Question 24

weakest to strongest repulsion

Answer 24

bonded to bonded pairs, lone to bonding, lone to lone

Question 25

vsepr

Answer 25

1 count to no of outer e- around the central atom
2 each bonded atom counts as 1 e-
3 if a -ve ion add an e-, if a +ve ion subtract an e-
4 divide by 2 to give the number of electron pairs
5 identify bonding/non bonding pairs decide shape

Question 26

linear

Answer 26

1 pair

Question 27

angular

Answer 27

2 bonding pairs and 1 or 2 lone pair

Question 28

trigonal planar

Answer 28

3 pairs

Question 29

trigonal pyramidal

Answer 29

3 bonding pairs and 1 lone pair

Question 30

tetrahedral

Answer 30

4 pairs

Question 31

trigonal bipyramidal

Answer 31

5 pairs

Question 32

octahedral

Answer 32

8 pairs