Covalent Bonding Flashcards
What is orbital theory ?
Covalent bonds are formed when orbitals , each containing 1 electron, overlap. This forma a region in space where an electron pit can be found. Therefore new molecular orbitals are formed.
What is it called when 2 electrons remain outside the covalent bond ?
A lone pair
What is a dative or coordinate bond.
Contains a shared pair of electrons with both electrons supplied by the same atom.
Draw the covalent bonding of carbon monoxide (CO).
In notes.
What are the properties of simple molecular micro molecules and why ?
Don’t conduct heat because no delocalised electrons. Soluble in organic solvents.
Low melting and boiling points because only intermolecular bonds need breaking not covalent bonds.
What are the properties of giant covalent macromolecules and why ?
Huh melting and boiling points because covalent bonds within the lattice need to be broken.
Very strong because the 3D crystal lattice involved many covalent bonds.
Doesn’t conduct because no delocalised electrons.
Give examples of simple molecular micro molecules.
O2 H2O CH4 (methane)
Give examples of giant covalent macromolecules.
Graphite , diamond , silicone dioxide / silica.
What are the properties of diamond and explain why.
Strongest natural substance due to having 4 carbon bonds in a 3D lattice which create rigidity.
Don’t conduct electricity because no delocalised electrons.
High melting and boiling points because 4 covalent bonds per carbon are hard to break.
What are the properties of graphite and explain why
Layers of graphite are held together by weak van der waals bonds which means the layers can slide over eachother.
Can conduct because only 3 carbon bonds are made and therefore there is one delocalised electron which can travel through the lattice.
High melting and boiling points due to needing to break 3 strong covalent bonds.
Solid crystal structure.
Draw the covalent bonding of NH4+
In notes
Draw the covalent bonding of NH3
In notes
What is the formula for ammonia
NH3
What is the formula of an ammonia ion.
NH4+
Draw the bonding of water (covalent)
In notes
