Covalent bonding

Question 1

Covalent bonding

Answer 1

Electrostatic attraction between a shared pair of electrons and the positively charged nucleus

Question 2

Coordinate (dative) bonding

Answer 2

When one atom donates both of the electrons shared between the two atoms

Question 3

What are the two exceptions to the octet rule?

Answer 3

1. Boron: with just 3 valenece electrons it forms relatively stable compunds
2. Beryllium: 2-4 valence electrons needed to form stable compound

Question 4

Which elements can have more than 8 electrons in their valence energy levels (expanded octet) ?

Answer 4

Non-metals below period 2

Because they are big atoms - large atomic radius. Up to 12 in their outer shell

Question 5

Resonance

Answer 5

When the lewis structure allows for the same arrangement of atoms but a different equally valid arrangement of electrons.

Question 6

What is the reality of the 𝝅 bond electrons in a resonance structure?

Answer 6

The 𝝅 bond electrons are delocalised throughout the entire molecule

Question 7

Why is benzene (C₆H₆) generally unreactive?

Answer 7

It behaves more like a saturated hydrocarbon than an unsaturated one due to the even distribution delocalised 𝝅 bond electrons, making it stable.