Chapter 5

Question 1

How many electrons are in shells 1,2,3 and 4?

Answer 1

1= 2
2= 8
3= 18
4= 32

Question 2

What is the shell number/ energy level known as?

Answer 2

The principle quantum number (n).

Question 3

What is an atomic orbital?

Answer 3

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

Question 4

What shape is an S- orbital?

Answer 4

Sphere shape

Question 5

How many s-orbitals are there in the groups 1+2?

Answer 5

1 s orbital (2 electrons)

Question 6

How many p-orbitals are there in the groups 3-8?

Answer 6

3 p-orbitals (6 electrons)

Question 7

What shape is a p-orbital?

Answer 7

dumb-bell shape. There are 3 at right angles to each other.

Question 8

How do orbitals fill?

Answer 8

In order of increasing energy.
1S2 2S2 2P6 etc

Question 9

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

Answer 9

The 3d sub shell is at a higher energy level.

But despite the 4s filling and losing electrons first.. its written after.

3P6 3d10 4S2

Question 10

How are orbitals drawn with electrons-in-box models?

Answer 10

They are drawn with opposite spins (1 arrow up and one arrow down).

Question 11

Why do the electrons in an orbital have opposite spins?

Answer 11

It helps counteract the repulsion between the negative charges since they are both electrons.

Question 12

How do the orbitals fill?

Answer 12

Each orbital fills singly first, like monopoly houses to minimise repulsion.

Question 13

What is ionic bonding?

Answer 13

The electrostatic attraction between positive and negative ions

Question 14

What is the structure of ionic compounds?

Answer 14

Each ion attracts oppositely charged ions in all directions, this forms a giant ionic lattice structure.

Question 15

Describe an ionic compounds melting point/boiling point?

Answer 15

They are solids at room temp as there isn’t enough energy to overcome the strong electrostatic forces of attraction between the oppositely charged ions in the giant ionic lattice.

So high temperature are needed to provide large amounts of energy.

Melting points are higher for lattices with ions with greater charges due to the stronger attraction between ions.

The size of the ions also impacts the ionic attraction.

Question 16

Describe an ionic compounds solubility?

Answer 16

Many dissolve in polar substances as they break down the lattice and surround each ion in solution.

If the compound is made with ions of large charges- then the attraction may be too strong for the water to break down the lattice.

Question 17

Describe an ionic compounds electrical conductivity?

Answer 17

As a solid it doesn’t conduct electricity. Once melted / dissolved in water it does.

solid- ions in fixed position there are no mobile charge carriers

liquid- lattice breaks down and ions are free to move as mobile charge carriers.

They are a conductor of electricity.

Question 18

What is covalent bonding?

Answer 18

The strong electrostatic attraction between a shared pair of electrons and the nuclei of the bonded atoms.

It is the overlap of atomic orbitals (each has one electron which gives a shared pair of electrons). The shared pair of electrons is attracted to the nuclei of both the bonding atoms.

Question 18

What is covalent bonding?

Answer 18

The strong electrostatic attraction between a shared pair of electrons and the nuclei of the bonded atoms.

It is the overlap of atomic orbitals (each has one electron which gives a shared pair of electrons). The shared pair of electrons is attracted to the nuclei of both the bonding atoms.

Question 19

What are paired electros that are not shared called?

Answer 19

Lone pairs

Question 20

What is a double covalent bond?

Answer 20

The electrostatic attraction is between two shared pairs of electrons and the nuclei of the bonding atoms.