shapes of molecules Flashcards
what is electron pair repulsion theory
a model used to predict and explain the shapes of moldcules and polyatomic ions
what determines the shape of a molecule or ion
electron pairs surrounding a central atom
what do electron pairs do
repel each other so they are as far apart as possible
what does the arrangement of electron pairs do
minimises repulsion and holds the bonded atoms in a definite shape
what does a solid line represent
a bond in the plane of the paper
what does a solid wedge represent
a bond coming out of the plane of the paper
what does a wedge represent
a bond going into the plane of the paper
why does a lone pair repel more strongly than a bonded pair
a lone pair is slightly closer to the central atom and occupies more space than a bonded pair
how many bonding regions is a double bond treated as
one
what shape and angle is made by 2 electron pairs
linear, 180°
what shape and angle is made by 3 electron pairs
trigonal planar, 120°
what shape and angle is made by 4 electron pairs
tetrahedral, 109.5°
