Bonding Flashcards
What is an ionic bond?
The electrostatic force of attraction between to oppositely charged ions.
What is an covalent bond?
The sharing of electron paors between atoms.
What is an dative covalent or co-ordinate bond?
A type of covalent bond where both of the electrons in the shared pair are donated by only on of the atoms.
Define electronegativity
Th ability of an atom to attract the bonding electrons in a covalent bond towards itself.
Define bond polarity
The separation of charge along a bond.
Explain what is meant by the term temporary dipole?
As electrons are continuously moving around the nucleus at any time there may be an uneven distribution of electrons making one region of the atom delta- and the other delta+.
Explain what is meant by the term permanent dipole?
If atoms that are covalent bonded together have different electronegativities then a polar bond forms. The atoms that is electronegative is delta- and the other delta+.
Explain what is meant by the term induced dipole?
When electron distribution around a molecule is influenced by a charged particle.
What is an hydrogen bond?
Electrostatic forces pf attraction between a hydrogen atom and highly electronegative atoms such as nitrogen, fluorine or oxygen.
What are van der waals forces?
What are intermolecular forces?
Forces that occur between molecules.
Name the types of intermolecular forces?
•induced dipole-dipole interactions (temporary)
•dipole-dipole interactions (permanent)
•hydrogen bonding
How does the anion charge affect the polarisation of ions?
A greater charge or ionic radius makes the anion more susceptible to polarisation.
How does the cation charge affect the polarisation of ions?
A greater charge or smaller ionic radius gives the cation a greater charge density and increases the effect on the charge cloud.
Explain the effect of hydrogen bonding on boiling points
As intermolecular forces increase, the
boiling poins increase also and they should show a general increase down a group.
This pattern is completely broken in groups 5, 6 and 7 due to the presence of nitrogen,
oxygen and fluorine at the top of these groups. Hydrogen bonding within these molecules forces the boiling points far higher than would be expected with only van der Waals forces.
Put the types of electron pairs in order based on strength
lone pair – lone pair > lone pair – bonding pair > bonding pair – bonding pair
What are lone pairs of electrons?
Spare electrons that are present in the
outer shell of the central atom and are not involved with the covalent bonding
What is the shape and bond angle of an molecule with 2 electron pairs?
Linear-180
What is the shape and bond angle of an molecule with 3 electron pairs?
Trigonal planar-120
What is the shape and bond angle of an molecule with 4 electron pairs?
Tetrahedral-109.5
What is the bond angle of an molecule with 3 electron pairs and 1 lone electron pair?
Tetrahedral-109.5
What is the bond angle of an molecule with 2 electron pairs and 2 lone electron pairs?
104
What is the shape and bond angle of an molecule with 5 electron pairs?
Trigonal bipyramind-90/120
What is the shape and bond angle of an molecule with 6 electron pairs?
Octahedral-90
