U1-2-3 - Molecule and Ion Shapes Flashcards
Bonding electron pairs
Electron pairs involved in covalent bonds
Non-bonding (lone) electron pairs
Electron pairs not involved in covalent bonds
Dative bond
A type of covalent bond formed when both bonding e− are donated by one atom.
The other atom accepts them into an empty orbital.
Electron pairs are negatively charged and ___________ each other. They are arranged in 3D to minimise repulsion and maximise separation.
repel
Electron pairs are negatively charged and repel each other. They are arranged in 3D to minimise ____________ and maximise separation.
repulsion
Electron pairs are negatively charged and repel each other. They are arranged in 3D to minimise repulsion and maximise _____________.
separation
Name this type of bond
A type of covalent bond formed when both bonding e− are donated by one atom.
The other atom accepts them into an empty orbital.
Dative bond
To use VSEPR, it is necessary to find out the no. of e− pairs surrounding a central atom.
To do this:
- ___________________________________________
- Add an e− for every negative charge
•Remove an e− for every positive charge
•Divide the total no. of e− by two to give the number of e− pairs.
Take the total number of valence e− on the central atom and add one for each atom attached
To use VSEPR, it is necessary to find out the no. of e− pairs surrounding a central atom.
To do this:
- Take the total number of valence e− on the central atom and add one for each atom attached
- _________________________________
•Remove an e− for every positive charge
•Divide the total no. of e− by two to give the number of e− pairs.
Add an e− for every negative charge
To use VSEPR, it is necessary to find out the no. of e− pairs surrounding a central atom.
To do this:
- Take the total number of valence e− on the central atom and add one for each atom attached
- Add an e− for every negative charge
•__________________________________
•Divide the total no. of e− by two to give the number of e− pairs.
Remove an e− for every positive charge
To use VSEPR, it is necessary to find out the no. of e− pairs surrounding a central atom.
To do this:
- Take the total number of valence e− on the central atom and add one for each atom attached
- Add an e− for every negative charge
•Remove an e− for every positive charge
•___________________________________
Divide the total no. of e− by two to give the number of e− pairs.
Name this shape
Tetrahedral
Name this shape
Trigonal bipyramidal
Name this shape
Octahedral
Name this shape
Trigonal planar
Which combination of bonding and non-bonding electron pairs has the lowest repulsion?
Bonding + bonding
Repulsion reduced due to attraction to positive nuclei
Which combination of bonding and non-bonding electron pairs has the highest repulsion?
Non-bonding + non-bonding
Shape when 6 bonding pairs are present
Octahedral
Shape when 4 bonding pairs are present
Tetrahedral
Shape when 3 bonding, 1 non-bonding pair are present
Trigonal pyramidal
Shape when 2 bonding, 2 non-bonding pairs are present
Angular (e.g. H2O)
Shape when 5 bonding pairs are present
Trigonal bipyramidal
Shape when 3 bonding pairs are present
Trigonal planar
