Dative Covelant Bonds

Question 1

when is a dative covelant bond formed

Answer 1

when an empty orbital of one atom overlaps with an orbital containing a lone pair of electrons of another atom

Question 2

how is a dative bond represented in diagrams

Answer 2

• an arrow starts from the atom providing the pair of electrons
• and points towards the atom the empty orbital

Question 3

what would the dot and cross diagram of hydroxonium, H3O+, look like

Answer 3

• the oxygen would be covelantly bonded with two hydrogen atoms on each side
• a dot and a cross (en electron from the hydrogen and the oxygen) would show this bond
• a hydrogen ion would also be bonded to one of the two lone pairs of electrons that oxygen has left
• with there being two crosses and no dots (2 electrons from oxygen and non from the H+
• then you would have your square brackets with the + sign

Question 4

what would the displayed formula of hydroxonium look like

Answer 4

• the oxygen would be covelantly bonded with two hydrogen atoms, represented by a line
• they would be 180 degrees from each other
• there would be an arrow pointing from the oxygen to the hydrogen ion (just written as an atom)
• with square brackets and a + sign

Question 5

why is the hydrogen ion bonding to oxygen is this way

Answer 5

• because the empty 1s orbital of H+ is overlapping with the orbital of the oxygen atom
• which contains those lone pair of electrons

Question 6

what is special about the dot and cross diagram of aluminium chloride (AlCl3) and why

Answer 6

• the aluminium atom in the molecule only has 6 electrons in its outer shell
• this is because it has an empty orbital (probs an s one)

Question 7

how does this correct itself

Answer 7

• by bonding with another AlCl3 molecule
• one of the atomic orbitals of a chlorine atom of one AlCl3 molecule that contains a lone pair overlaps with the empty orbital of the Al atom of another molecule
• the same thing happens vice versa

Question 8

what are these molecules therefore bonded together with and what kind of structure does it make

Answer 8

• dative covelant bonds

- making each molecule act like a bridge to form a chain