Bond Polarity Flashcards
when is a covalent bond polar?
when two atoms in a covalent bond have different electronegativities
when is a covalent bond non-polar?
when two atoms in a covalent bond have the same electronegativity eg h2
which atom will electrons be drawn towards in a polar bond?
the more electronegative atom
why is the electron distribution asymmetric in a polar bond?
the negative charge centre and positive charge centre do not coincide with each other
what partial charge does the more electronegative atom get?
the more electronegative atom gets a partial charge of δ- (delta negative)
what partial charge does the less electronegative atom get?
the less electronegative atom gets a partial charge of δ+ (delta positive)
what is the affect of an increase in the difference in electronegativity in a bond?
the greater the difference in electronegativity the more polar the bond becomes
what is a dipole moment?
the calculation of the net polarity at either end of the dipole
how is the direction of the dipole moment shown?
an arrow
which end of the dipole does the arrow point to?
the arrow points to the partially negatively charged end of the dipole:
what 2 things are considered to determine whether a molecule with more than two different atoms is polar?
-the polarity of each bond
-how the bonds are arranged in the molecule
why do some molecules have polar bonds but are overall not polar?
because the polar bonds in the molecule are arranged in such way that the individual dipole moments cancel each other out (the molecule is symmetrical)
what is dipole?
a polar bond which has oppositely charged ends
