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What are compounds
A compound is formed when two or more elements chemically combine
How many different types of bonding are there
3;
Ionic bonding
Covalent bonding
Metallic bonding
Give an dxample of a IONIC bond
Sodium chloride
What type of elements is a IONIC bond between
a NON-METAL and a METAL
From where are the electrons transferred in IONIC bonding
From the METAL atom to the NON METAL atom
Why are electrons transferred in IONIC bonds
To create a FULL outer shell
After the electrons are transferred what are the elements now called
IONS
What are ions
Ions are when the element has the same number of protons and neutrons but a different number of electrons
What are the two ways which atoms can get a full outer shell
By TRANSFERING electrons - ionic bonding
By SHARING electrons - covalent bonding
Can the inner levels of electrons be involved in chemical bonding
NO - only the outer shell of electrons
why are some atoms that are stable and INERT
They have a full outer shell
What two states can ions be
Positive charged
Negative charged
What is a short definition of IONIC bonding
A strong electrostatic attraction between oppositely charged ions
What is a positively charged ion called
A CATION
What is a negative ion called
an ANION
How are ionic bindings shown in a diagram
Using DOT - CROSS diagrams
What are electrons drawn as in a dot cross diagram
Either dots or crosses
What level of electrons do dot cross diagrams show
The outer shell of electrons
What should every atom end up with in a dot cross diagram
A full outer shell
What type of metals are most likely negative ions
NON METALS
If three electrons are transferred from a metal atom what does it become
It is M³+
If one electron is transferred to a non metal atom what does it become
NM^-
What depends on the number of electrons that an atom gains or loses
It’s GROUP NUMBER (how many electrons there are in its outer shell)
Why do group 8 not Form ions?
They alr have a full outer shell
What is oxidation
Gain of oxygen
Loss of electron (hydrogen)
What is reduction
Loss of oxygen
Gain of electron (hydrogen)
What is a redox reaction
when an reaction has both oxidation and reduction - if oxidation happens reduction HAS TO happen
Whats a mnemonic which can help us REMEBER oxidation and reduction
OILRIG - oxidation is loss reduction is gain
LEO the lion says GER - Loss of Electrons is Oxidation, Gain of Electrons is Reduction
What does this half equation show
Na - e —> Na+
Oxidation
What does this half equation show
K+ + e —> K
Reduction
What are the 4 properties of ionic compounds
High mp and bp
Dissolve in water
Conduct electricity ONLY when molten or in a solution - NEVER SOLID
Insoluble in organic solvents
Why do ionic compounds have high mp and bp
Hard to change the state of compound
Because of the strong forces of attraction between the NEGATIVE non metal ions and the POSITIVE metal ions
So to change state —> must OVERCOME the strong forces of attraction
Need a LARGE AMOUNT OF ENERGY to do this
This means high boiling and melting points
Why can ionic compounds NOT conduct electricity in a SOLID
In a SOLID - atoms are in a fixed position in the giant ionic lattice
Ions can’t move
So current is unable to flow
Why can ionic compounds conduct electricity in a solution or molten?
Solid has been dissolved to form ions in the water - no longer in a fixed position
Ions can move
Current can flow
SAME FOR MOLTEN ionic compounds
Would you expect tap water to conduct and why
Yes - tap water contains dissolved ionic compounds
Note 
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