3.1.3 - Bonding Flashcards
Definition of ionic bonding
The electrostatic attraction between positive and negative ions. They are non- directional
In ionic bonding what loses electrons and what gains electrons
Metals lose electrons
Non- metals gain electrons
How can your represent an ionic bond ?
What can’t you forget
Using a dot and cross diagram
Don’t forget the charges
Definition of covalent bonding
The electrostatic attraction between a shared pair of electrons and the nuclei of two atoms. They are directional.
How many covalent bonds does group 4 make ?
4
How many covalent bonds does group 3 make ?
3 or more
How many covalent bonds do group 2 make?
2 or more
How many covalent bonds do group 1 make ??
1 or more he p
What is a dative covalent bond ??
Where both electrons come from the same atom
How are dative covalent bond presented ?
The bond is shown by an arrow rather than a straight line
Definition of metallic bonding
The electrostatic attraction between positive ions and delocalised electrons. They are non- directional.
What is the trend across a period of melting point in metals ?
Increase
Charge increases
Electrons increase
Therefore strength of metallic bond is increased
What is the trend of melting point down a group of metals
Decreases Size of ion decreases Charge stays the same Electrons stay the same Mettalic bond strength decreases
Ionic Mp and Bp Conductivity(solid) Conductivity (molten) why? Conductivity (aq) why? Strength why ? Solubility why?
High No Yes -ions free to move Yes-ions free to move Brittle- dislocation lead to layers moving and then repelling each other High - water is polar separates the ions
Metallic
Mp and bp Conductivity(solid) why? Conductivity (liquid) why? Conductivity (aq ) why? Strength Why ? Solubility why ?
High Yes Yes Insoluble Strong can slide over each other Insoluble
Giant covalent
Mp and bp Conductivity (solid) Conductivity (liquid) Conductivity (aq) Strength Solubility
Very highly No No Insoluble Strong for some Insoluble bonds must be broken
Diamond
Structure Bp and mp Conductor Strength Solubility
Giant covalent
Very high bp and mp many strong covalent bonds need breaking
Poor conductor no mobile electrons or ions
Very strong - rigid tetrahedrald arrangement
Insoluble- many covalent bonds must be broken
Graphite
Structure Bp and mp Conductivity Strength Solubility
Very high melting point and boiling point many strong covalent bonds need breaking
Conducts some electrons are free to move
Brittle weak can der waals between layers which can slide over each other
Insoluble- many covalent bonds must be broken