Shapes of molecules

What is the Valence shell?

the outermost shell of an atom where the electron sharing takes place

What is the electron pair repulsion theory?

pairs of electrons repel each other (as both have -ive charge) so they adopt certain shapes and bond angles

Linear shape

-180 degrees

-2 bonding pairs/regions

-no lone pairs on central atom

Trigonal planar shape

• 120 degrees

• 3 bonding pairs/regions

• No lone pairs

Tetrahedral shape

• 4 bonding regions/pairs

• 109.5 degrees

• no lone pairs

Octahedral shape

-6 bonding pairs/regions

- 90 degrees

No lone pairs

Pyramidal shape

• 3 bonding pairs/regions

• 107 degrees

• 1 lone pair

Non-linear shape

- 2 bonding regions/pairs

- 2 lone pairs on central atom

- 104.5 degrees