Electronic Structure 2.2.1

Question 1

Shells are made up of what

Answer 1

Sub-shells

Question 2

What are subshells made up of

Answer 2

Atomic orbitals

Question 3

Name the subshells

Answer 3

S, P, D, F

Question 4

Name the orbitals

Answer 4

SPDF

Question 5

What is S subshells made up of

Answer 5

1 single s orbital

Question 6

What is P subshell made up of

Answer 6

3 p orbitals

px
py
pz

Question 7

What is D subshell made up of

Answer 7

5 d orbitals

Question 8

What is f subshell made up of

Answer 8

7 f orbitals

Question 9

What is the term shells commonly known as

Answer 9

Principle energy level or principle quantum number

Question 10

What is principle quantum number n

Answer 10

A number representing the relative overall energy of each orbital. The sets of orbitals with the same n value are referred to as electron shells or energy levels

Scientists have given each shell a number n- this is referred to as the principle quantum number e.g. first shell has PQN of 1
seconds shell has pqn of 2
third shell has pqn of 3
and so on

-it’s used in the equation 2n squared to find maximum number of electrons in each shell

Question 11

What does an increase to PQN represent

Answer 11

Increase to principle quantum number represents an increase in relative overall energy as we move further from the nucleus
n=2 is further from nucleus than n=1 so it’s got more relative energy

As we mover further from the nucleus the relative energy increases due to decrease interaction between nucleus and electrons orbiting it so the higher the pqn the further the electrons from the nucleus the higher the relative overall energy

Question 12

Define sub-shell

Answer 12

A group of the same type of atomic orbitals within a shell

Question 13

Define atomic orbitals

Answer 13

A region around the nucleus that can hold up to 2 electrons with opposite spins

Question 14

What is the shape of an s orbital

Answer 14

Sphere

Question 15

What is the shape of a p orbital

Answer 15

Dumb bell

Question 16

How do you represent the opposite spins in an orbital

Answer 16

in the box draw two arrows one facing upwards one facing downwards

Question 17

An s sub-shell can hold how many orbitals and therefore how many electrons

Answer 17

S sub-shell= 1 orbital so it can hold a maximum of 2 electrons

Question 18

An p sub-shell can hold how many orbitals and therefore how many electrons

Answer 18

P sub-shell= 3 orbitals so it can hold a maximum of 6 electrons

Question 19

An d sub-shell can hold how many orbitals and therefore how many electrons

Answer 19

D subshell= 5 orbitals, each orbital can hold 2 electrons so it can hold a maximum of 10 electrons

Question 20

Shell 1 contains what sub-shells

Answer 20

1s sub-shell

Question 21

Shell 2 contains what sub-shells

Answer 21

2s, 2p sub-shells

Question 22

Shell 3 contains what sub-shells

Answer 22

3s, 3p, and 3d subshells

Question 23

Shell 4 contains what sub-shells

Answer 23

4s, 4p, 4d, 4f sub-shells

Question 24

What is the AufBau principle

Answer 24

Electrons fill the sub-shells with order of increasing energy. The order is 1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p for the elements hydrogen to krypton

Question 25

What is Hund’s rule

Answer 25

Within a sub-shell the orbitals are first occupied singly by unpaired electrons. The electrons only pair up when there are no empty orbitals left in the sub-shell

BUSSESS!!!!!!!!!!!!!

Question 26

In an orbital the 2 electrons must have…

Answer 26

Opposite spins

Question 27

What is meant by ‘opposite spins’ when referring to the two electrons in an orbital

Answer 27

one electron spins clockwise and one anticlockwise

Question 28

How do you work out the maximum number of electrons in a shell or energy level

Answer 28

By using the formula 2n2

n = number of the shell (energy level)

Question 29

What does the period number tell you about electronic structure of an atom

Answer 29

Numbers of the periods – tells you which shell is being filled

Question 30

How do electrons know which orbital to go into first e.g. 3d or 4s

Answer 30

• Electrons enter the lowest energy orbital available (4s is lower energy than 3d when empty)

Question 31

How do you work out which block an element belongs to

Answer 31

Look at the number of the period + the block to work out which sub shell the highest energy electrons are in on the atom

Question 32

Learn the blocks on the periodic table s, p, d, f

Answer 32

It is in the Gap task: Atomic and Electron Structure, Isotopes and Formulae test booklet
Go to Question 10 there is a grid on that page and some questions on the bottom for practice

Question 33

What happens to the energy of the sub-shells as we move further away from the nucleus

Answer 33

As we move further away from the nucleus the energy of the sub-shells increases

Question 34

Why do we put electrons into individual orbitals before filling them up as pairs

Answer 34

As the orbitals have the same energy, we put electrons in individually because the electrons in the same orbital repel

Question 35

What do we fill up first 4s or 3d

Answer 35

Fill 4s before 3d because it has lower energy than 3d when its empty

Question 36

When 4s contains electrons as it fills up before 3d what happens to the electrons when they have to leave a sub-shell

Answer 36

When 4s contains electrons it is higher in energy than 3d, and electrons leave from 4s before 3d

Question 37

Write out the full Electron configuration of Silicon and the Short hand version

Answer 37

Silicon = 14 e-

Full electron configuration :
1s2 2s2 2p6 3s2 3p2

• Shorthand electron configuration [Ne] 3s2 3p2

Question 38

What do we not write when writing the electron configuration of an element e.g. Silicon

Answer 38

The GCSE version of 2, 8, 4

Question 39

What 2 elements do not have expected electron structure

Answer 39

Chromium and Copper

Question 40

Why do Cu and Cr not have expected electron Structure

Answer 40

Cu and Cr do not have the expected electron structure because the atom is more stable with half full or full sub shells

Question 41

What is the Electron Configuration for Chromium

Answer 41

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

Question 42

What is the electron Configuration of Copper

Answer 42

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

Question 43

What happens when an anion is formed

writing electron configuration for ions

Answer 43

More electrons are added when a negative ion (anion) is formed-

Question 44

What happens when a cation is formed

Answer 44

The highest energy electrons are lost when a positive ion (cation) is formed.

Question 45

What is affected within the electronic structure of the atom when it becomes an ion

Answer 45

The highest energy sub-shell
if an atom becomes a cation then it will loose electrons from the highest energy sub-shell and if an atom becomes an anion then it will gain electrons and expand on the highest energy sub-shell

Question 46

In an s orbital the greater the shell number n the greater the…

Answer 46

Radius of the s orbital

Question 47

The p orbitals are…

Answer 47

At right angles to eachother

Question 48

In a p orbital the greater the shell number the…

Answer 48

Further away the p orbital is from the nucleus

Question 49

The highest energy level in the third shell overlaps with the lowest energy level of the fourth shell. True or false

Answer 49

True, 4s has slightly less energy than 3d when empty so is filled up before the 3d

Question 50

Chloride Ion is isoelectronic with what

Answer 50

An Argon Atom