Chapter 5 (approved)

Question 1

What are atomic orbitals?

Answer 1

A region around the nucleus which can hold up to two electrons with opposite spin

Question 2

S-orbitals:
number, shape, how they change with ‘n’

Answer 2

Each shell from n=1 contains 1 s-orbital
Sphere
The greater the shell number n, the greater the radius of its s-orbital

Question 3

p-orbitals:
number, shape, how they change with ‘n’

Answer 3

Each shell from n=2 contains three p-orbitals
Dumbell
The greater the shell number n, the further the p-orbital is from the nucleus

Question 4

How many electrons can fill the first four shells?

Answer 4

2,8,18,32

Question 5

Number of d-orbitals

Answer 5

Each shell from n=3 contains 5 d-orbitals

Question 6

Number of f-orbitals

Answer 6

Each shell from n=4 contains 7 f-orbitals

Question 7

Sub-shells

Answer 7

A group of the same type of orbitals within a shell

Question 8

Explain the blocks in the periodic table

Answer 8

Table is divided into blocks based on their highest energy sub-shell

Elements in s-block (Left):
Highest energy electrons in the s-subshell

Elements in p-block (Right):
Highest energy electrons in the p-subshell

Elements in d-block (Centre):
Highest energy electrons in the d-subshell

Question 9

Why is the 4s subshell filled and emptied before the 3d subshell?

Answer 9

The 4s subshell is at a lower energy than the 3d subshell so it is filled first
The 4s and 3d energy levels are close together, so once filled, the 3d energy level falls below the 4s energy level.

Question 10

What is ionic bonding?

Answer 10

Electrostatic attraction between positive ansd negative ions

Question 11

What structure do ionic compounds have?

Answer 11

Giant ionic lattice, where each ion is surrounded by oppositely charged ions

Question 12

Ionic compounds: melting and boiling points

Answer 12

Mostly solid at room temp as there isn’t enough energy to overcome the strong ionic bonds in the lattice
High temps are required to overcome the strong ionic bonding in the giant ionic lattice, so they have high melting and boiling boiling points

Question 13

Factors that affect the melting and boiling points of ionic compounds

Answer 13

Size of ionic charges
Relative size of the ions (only if there is a large difference)

Question 14

Solubility of ionic compounds

Answer 14

Many dissolve in polar solvents like water, as the molecules break down the lattice and surround each ion in solution

Question 15

What affects the solubility of ionic compounds

Answer 15

Size of ionic charge - in a compound with large charges the ionic attraction may be to strong for water molecules to break the lattice, making the compound not very soluble

Question 16

Solubility requirements

Answer 16

Ionic lattice msut be broken down
Water molecules must attract and surround the ions

Question 17

Ionic compounds electrical conductivity when solid

Answer 17

Ionic compounds do not conduct electricity (non-conductors) when solid because the ions are in a fixed position in the giant ionic lattice so there are no mobile charge carriers

Question 18

Ionic compounds electrical conductivity when molten or dissolved in water

Answer 18

when molten or dissolved in water they
can conduct electricity becasue the solid ionic lattice breaks down so the ions are free to move as mobile charge carriers

Question 19

Covalent bond

Answer 19

A shared pair of electrons

Question 20

What does a displayed formula show?

Answer 20

The relative positioning of atoms and the bonds between them as lines

Question 21

Dative covalent bond

Answer 21

A covalent bond where the pair of electrons is supplied by one of the atoms

Question 22

Average bond enthalpy

Answer 22

A measure of covalent bond strength