C3 Bonding Flashcards
What is ionic bonding?
The TRANSFER of electrons with a METAL AND NON METAL.
This creates a strong bond with strong electrostatic forces
What does a dot and cross diagram show?
Explain?
Covalent compouds
You draw 2 atoms woth there electrons either being dots or corsses (1 for each element)
You can then draw these again but with the extra electron changing atom
Name some ionic compouds?
MgO
MgCl_2
Na_2O
What are the benifits of a dot and cross diagram?
It is simple
It shows the change in the compoud
What are the disadvantages of a dot and cross diagram?
They don’t show the structure of the coupound
They arn’t to scale
What is the structure of an ionic compoud?
Giant ionic lattice
This is a regular lattice structure
What is a giant ionic lattice?
A closely packed regular lattice which is connected by ionic bonds. This means that the electrostatic forces holding the lattice together are really strong. This means that it has a high melting and boiling point
It is made up of oppositly charged ions in all directions of the lattice
What are the similar properties of an ionic compound?
They have a high melting and boiling point due to the strong electrostatic forces. Lots of energy are needed to break these
They can’t conduct electricity when they are a solid but when they are in a liquid they will conduct electricity
Some ionic compounds disolve in water. The ions will seperate and will be free to move around. This means that they will conduct electricity
How do you work out the empirical formula of an ionic compound from a diagram or from a dot and cross diagram?
Dot and cross diagram
Count the electrons to find out what element they are
And look at how many of each element there are
DIAGRAM
Look at the amount of electrons each element would need to get to a charge of 0
Balnce them
Eg
K (potassium) forms 1+ ions
O (oxygen) forms 2- ions
You would need 2 K atoms to make the overal charge 0
Therefore the empirical formula is K_2O
What is covalent bonding?
When non metal’s share electrons to complete there outer shells
This can also happen in non metal compounds
Are covalent bonds strong or week?
Why?
They are strong
The electrons are attracted to both of the positivly charged nuclei. This creates strong electrostatic bonds
How do you draw a dot and cross diagram for covalent bonding?
They outer shellss of the electrons need to be overlaping
There will be pairs of electrons inside the shared area
There will be the same amount of crosses as dots in each overlap
What is a displayed formula
Explain it?
When you draw lines to show the covalent bonding - 1 line = 1 bond …
What are the advantages of a displayed formula?
Shows how the atoms are connected in large molecules
What are the disadvantages of a displayed formula?
It is 2D
It doesn’t show where the covant bond comes from