Electrons and Bonding

Question 1

How many electrons can be in the first shell?

Answer 1

2

Question 2

How many electrons can be in the 2nd shell?

Answer 2

8

Question 3

How many electrons can be in the 3rd shell?

Answer 3

18

Question 4

How many electrons can be in the 4th shell?

Answer 4

32

Question 5

What are shells?

Answer 5

These are energy levels.

Question 6

What happens as the shell number increases?

Answer 6

The energy increases.

Question 7

What is meant by the principal quantum number, n?

Answer 7

This is the shell number.

Question 8

What are shells made up of?

Answer 8

Atomic orbitals.

Question 9

What is an atomic orbital?

Answer 9

This is a region around the nucleus that can hold up to two electrons.

Question 10

In which way do the electrons in atomic orbitals spin?

Answer 10

They spin in the opposite direction to each other.

Question 11

How many electrons can an orbital hold?

Answer 11

No more than 2.

Question 12

What are the different types of orbitals?

Answer 12

s,p,d,f

Question 13

What does each different type of orbital have?

Answer 13

A different shape.

Question 14

What is the shape of an s orbital?

Answer 14

It is a sphere.

Question 15

What shells contain s orbitals?

Answer 15

Each shell from n=1 contains one s orbital.

Question 16

What increases the radius of an s orbital?

Answer 16

The more shells, the bigger the radius.

Question 17

What is the shape of the electron cloud in a p orbital?

Answer 17

It is dumb bell shaped.

Question 18

How many p orbitals are present in each shell?

Answer 18

3

Question 19

At what angle are p shells to each other?

Answer 19

They are at right angles to one another.

Question 20

Which shell contains no p orbitals?

Answer 20

n=2

Question 21

What are the 3 p orbitals referred to as?

Answer 21

Px, Py, Pz

Question 22

What happens as the shell number increases?

Answer 22

The p orbital moves further away from the nucleus.

Question 23

How many d orbitals are present in each shell above n=3?

Answer 23

5

Question 24

How many f orbitals are present in each shell above n=4?

Answer 24

7

Question 25

What are orbitals of the same type in the same shell known as?

Answer 25

Sub-shells

Question 26

What does each new shell gain?

Answer 26

A new type of orbital.

Question 27

Within each shell, the new type of sub-shell added has a higher what?

Answer 27

Energy

Question 28

The highest energy level in the third shell overlaps with what?

Answer 28

The lowest energy level in the 4th shell.

Question 29

Why does the 4s shell fill before the 3d shell?

Answer 29

The 4 s sub shell has a lower energy.

Question 30

Why do electrons repel each other?

Answer 30

They are all negatively charged.

Question 31

What must the two electrons in each orbital have?

Answer 31

Opposite spins.

Question 32

Why do the electrons spin in opposite directions?

Answer 32

To overcome electron repulsion.

Question 33

What do orbitals all have within the sub-shell?

Answer 33

The same energy.

Question 34

What happens before pairing starts?

Answer 34

One electron occupies each orbital in the sub-shell/

Question 35

How does filling each orbital with one electron before pairing affect repulsion?

Answer 35

It reduces it.

Question 36

What does the electron configuration of an atom show?

Answer 36

This shows how sub-shells are occupied by electrons.

Question 37

What is short hand notation useful for?

Answer 37

It is useful for emphasising similarities in the electron configurations of the outer shell.

Question 38

What are cations?

Answer 38

These are positive ions.

Question 39

What are anions?

Answer 39

These are negative ions.

Question 40

When are cations formed?

Answer 40

When atoms lose electrons.

Question 41

When are anions formed?

Answer 41

When atoms gain electrons.