EL 5 Flashcards
(17 cards)
what are the features of covalent bonding and what does it achieve
elements in compounds share outer electrons to get full outer shell
makes compound more stable
dot and cross diagram
could have lone pairs
e.g 2 hydrogens
what is a dative covalent bond
one element donates 2 pairs of electrons
e.g carbon monoxide
are electrostatic attractions between simple molecules weak and if so why
yes
takes little energy to break bonds
low melting and boiling points
do simple covalent molecules conduct electricity explain answer
they do not
have no charged particles
do simple covalent molecules dissolve in water explain answer
no (no charge)
arent polar so cant dissolve
what is a lone pair and what effect do they have on the configuration
extra electrons not used in a covalent bond
determines shapes of molecules (repel as far a part as possible)
repel bonding pairs of electrons
how much does a lone pair decrease the bond angle
2.5 degrees per lone pair
what is the electron pair repultion theory
shape of molecule is determinded by lone pairs
pairs of electrons repel eachother
like charges repel (electron = - charge)
electron pairs move as far a part as possible to reduce repultion
what are the seven shapes molecules could be called
linear
non linear
pyramidal
bipyramidal
planar triangular
tetrahedral
octahedral
features of a linear molecule shape
(bond angle, lone pairs, bonding pairs, reigons of charge)
bond angle- 180
lone pairs- 0
bonding pairs-2
reigons of charge-2
features of a planar triangular molecule shape
(bond angle, lone pairs, bonding pairs, reigons of charge)
bond angle- 120
lone pairs- 0
bonding pairs-3
reigons of charge-3
features of a tetrahedral molecule shape
(bond angle, lone pairs, bonding pairs, reigons of charge)
bond angle- 109.5
lone pairs- 0
bonding pairs- 4
reigons of charge- 4
features of a pyramidal molecule shape
(bond angle, lone pairs, bonding pairs, reigons of charge)
bond angle- 107
lone pairs- 1
bonding pairs- 3
reigons of charge- 4
features of a non linear molecule shape
(bond angle, lone pairs, bonding pairs, reigons of charge)
bond angle- 104.5
lone pairs- 2
bonding pairs- 2
reigons of charge- 4
features of a bipyramidal molecule shape
(bond angle, lone pairs, bonding pairs, reigons of charge)
bond angle- 90 + 120
lone pairs- 0
bonding pairs- 5
reigons of charge- 5
features of a octahedral molecule shape
(bond angle, lone pairs, bonding pairs, reigons of charge)
bond angle- 90
lone pairs- 0
bonding pairs- 6
reigons of charge- 6
why do lone pairs repel more than bonding pairs
lone pairs are more concentrated regions of charge
so repel stronger than bonding pairs
