Ionic bonding Flashcards
What happens in ionic bonding?
Atoms lose or gain electrons to form charged particles (called ions) which are then strongly attracted to one another (because opposite charges attract +-).
What type of elements want to lose their electrons?
Those over the left-hand side of the periodic table (e.g. sodium).
Why do elements over the left-hand side of the periodic table want to lose electrons?
Because they contain just one or two electrons in their outer shell, and once they are lost they will have full shells left.
What do elements without full shells do?
They try to have the same electronic structure as a noble gas.
When an element loses an electron what does it become?
An ion.
What do ions tend to do?
Leap at the first passing ion with an opposite charge and stick to it.
What elements have outer shells which are nearly full?
Those on the right-hand side of the periodic table.
What are the elements on the right-hand side of the periodic table keen to do?
Gain that extra one or two electrons to fill their shells.
When an element gains an electron what does it become?
An ion.
Give an example of ionic bonding?
Between sodium and chlorine.
How does ionic bonding occur between sodium and chlorine?
- The sodium atom gives up its outer electron and becomes an Na+ ion.
- The chlorine atom gains the electron from sodium and becomes a Cl- ion.
- They then latch onto each other because opposite charges attract.
What structure are ionic compounds?
Giant ionic lattices.
In an ionic compound’s giant ionic lattice structure, what is it like?
- The ions form a closely packed regular lattice arrangement.
- There are very strong electrostatic forces of attraction between oppositely charged ions, in all directions.
What is an example of one giant ionic lattice?
A single crystal of sodium chloride (salt).
Why do salt crystals tend to be in cuboid shapes?
Due to their giant ionic lattice structure.
What do ionic compounds all have?
Similar properties.
What similar properties do all ionic compounds have?
- High melting points.
- High boiling points.
Why do ionic compounds have high melting and boiling points?
Due to the strong attraction between the ions in the giant ionic lattice.
How does the strong attraction between the ions cause the ionic compounds to have high melting and boiling points?
Because it takes a large amount of energy to overcome this attraction.
When do ionic compound conduct electricity?
When they are molten.
What happens when ionic compounds melt?
The ions are free to move and they’ll carry electric current.
What do ionic compounds do in water?
They dissolve easily.
What happens when ionic compounds dissolve in water?
The ions separate and are all free to move in the solution, so they’ll carry electric current.
