Covalent Bonding

state which elements form covalent bonds:

non - metal + non - metal

Define covalent bond:

The strong electrostatic forces of attraction between two nuclei and the shared pair of electrons between them

Define bond length:

The distance between the two covalently bonded nuclei (at positions of maximum attraction)

How does bond length influence bond strength?

As bond length decrease, bond strength increases

State 3 factors that bond length depends on:

1. atomic radii

2. shielding

3. attraction

Explain why the Si-H and C-H bond lengths are different:

silicon has a larger atomic radius than carbon​

so has more shielding​

which reduces the attraction for the bonded electrons

What is a “lone pair”?

a pair of electrons in the outer shell which are not used to form a covalent bond

What period can the expansion of the octet occur in and why?

Period 3 and beyond - they have a 3d subshell

What is a dative bond?

When an atom uses a lone pair of electrons to form a covalent bond

What condition a dative bond can form in?

the acceptor atom must be electron deficient (there are available orbitals for the electron to occupy)

Do shorter or longer bond lengths require more energy to break?

Shorter

because there is greater attraction between nuclei and electron