Structure and bonding Flashcards
What is covalent bonding?
Covalent bonds are held together by electrostatic forces of attraction between positively charged nuclei and negatively charged shared electrons.
What is a covalent network structure?
A covalent network structure consists of a giant network of covalently bonded atoms.
If two atoms have the same electronegativity, what will happen?
The electrons will be shared equally therefore it is a non-polar covalent bond.
If one atom has a slightly higher electronegativity than the other what will happen?
The atom with the greater electronegativity will have the bonding electrons closer to it making that atom slightly negative and the other atom slightly positive. This is know as a polar covalent bond.
What will happen is one atom has a massive difference in electronegativity to another?
The atom with the greatest electronegativity will have the bonding electrons pulled so close to it that in effect it has gained those electrons and the other atoms have lost those electrons making it an ionic bond.
What are the three structures that compounds may be in a solid state?
- Ionic
- Covalent network including silicon dioxide and silicon carbide
- Covalent molecular
What are the 4 duffest types of arrangement of a compound?
- Linear
- Angular
- Trigonal Pyramidal
- Tetrahedral
What is intermolecular bonding?
Intermolecular bonding are bonding between molecules.
What is intramolecular bonding?
Intramolecular bonding are bonding within molecules
Why are some compounds with the presence of polar bonds not a polar molecule?
Because the molecule is not symmetrically arranged.
What are the main examples of non-polar molecules?
- Hydrocarbons
- Carbon dioxide
What are the main examples of polar molecules?
- Organic compounds such as ethanol
- water
How do you test the polarity of a liquid?
Rubbing a plastic rod creates an electric charge which can be used to attract objects. Since polar molecules have a permanent dipole, they will be attracted to the rod. Non-polar molecules are not affected by the charged rod.
What are London dispersion forces?
London dispersion forces are the weakest of the intermolecular forces but in the absence of any other any they are important (I.e. holding a polar bond together)
What is the relationship between the number of electrons and the strength of the London dispersion forces?
The greater number of electrons there are present in a molecule, the stronger the London dispersion forces are.