Secondary bonding Flashcards
(22 cards)
Delta Plus
Less electronegative and loses more ‘control’ of atom
Delta minus
more electronegative and had greater ‘control’ over the shared electron
what defines polar?
If two different atoms are bonded that have different level of electronegativity
non-polar
relatively similar electronegativity
true or false: All covalent bonds are polar
true
What is the exception of the polar bonding rule
C H
why is shape important (clue, polar and non-polar)
Determines the importance in whether it is a polar or non-polar molecule
How do you determine if the molecule is polar?
If there is a positive and negative end of the molecule, it is a polar molecule.
Positive-negative attraction making the bond stronger. Is it polar or non-polar
Polar
Can a molecule be non-polar but contain polar bonds
yes
what is secondary bonding?
The force of attraction that operates between neighbouring molecules. It is also called ‘ intermolecular’ interactions. Occurs in covalent molecules
Three types of secondary bonding
Dispersion forces
Dipole- dipole
Hydrogen bonding
What are the properties of secondary bonding?
They are electrostatic, weaker than primary bonds, hold molecules to each other in liquid and solid states
Dispersion forces
Weakest form of secondary bonding
only sub bonding in secondary bonding that includes non-polar
non-polar substances in dispersion forces properties
have no permanent diple
Due to the non-symmetrical distribution of charge a temporary dipole is formed
temporary dipole
they have induced polarity and are still weak. Can additionally be formed when molecules collide
how does a dispersion force have a larger attraction?
the close the molecules can get, the stronger the attraction will be.
Larger molecules= greater dispersion forces
Dipole-dipole interaction properties
Only occurs with polar molecules. positive ends bond with negative ends
symmetrical distribution of charge over them
Has a stronger force than dispersion forces but eaker than hydrogen bonding
Hydrogen bonding properties (2 answers)
Strongest type of secondary bonding
It is a form of dipole-dipole interaction
when is hydrogen bonding formed
hydrogen atom in one molecule is attracted to the non-bonding electron pair of a small, highly electronegative atom (N,O or F)
Hydrogen bonding pattern
Low electronegativity (hydrogen) + high electronegativity (Neon, Oxygen and Fluorine)
What does secondary bonding determine
The melting and boiling point
