unit 1 - bonding

Question 1

What are the different type of bonding?

Describe: Ionic and Covalent

Answer 1

• Ionic: bond is formed based on electrostatic attraction of two oppositely charged ions
• covalent bonds: where electrons are shared b/w two atoms (in rare cases electrons can also be shared b/w three or more atoms)

Question 2

What is the trend of EN in the periodic table

also define EN

Answer 2

Increasing EN left to right
Increasing EN down to up
- tendency of an atom participating in a covalent bond to attract the bonding electrons

Question 3

Which molecules don’t follow the octet rule?

Answer 3

• molecules with an odd number of electrons or less than 8 in neutral form
• elements below the second row (valence expamded, or hypervalent)

Question 4

Define constituional isomers (structural isomers)

Answer 4

• moleciles that have the same formula but different structures (to interconvert the structures you would need ot break the bonds)

Question 5

Geometry and VSEPR Theory (Valence sheel electron pair repulsion theory)

Draw tetrahedral, triganol planar, and linear

define each and their bond angles

Answer 5

1. 4 groups of electrons around it; either bonding or nonbonding electrons; 109.5; one way forward (wedge) one way backward (dash line)
2. 3 groups of electrons; 120; can use wedge and dash line for side view but can just do regular lines for top view
3. 2 groups of electrons; 180

Question 6

Resonance structures

what is resonance?

and important points (like arrows and brackets around it typa thing)

Answer 6

• representation of an electronic structure of a molecule in terms of contributing structures; these are not real compounds and cannot be isolated
• the structures are intercahnged only by moving electrons ATOMS MUST NOT MOVE

Question 7

Resonance structures

How do you determine the major and minor contributing structures?

Answer 7

1. EN: the more EN is the major
2. Octet rule: wanting to have a full valence shell with the formal charge
3. Stable molecule prefer to avoid charges

Question 8

Describe the atomic orbitals

Answer 8

1. 1s
2. 2s
3. 2p: px,py,pz; dumbell shaped orbitals
   - orbitals closest in energy form the strongest bonds

Question 9

What are the rules for filling orbitals with electrons

Aufbau principle, Pauli exclusion principle, Hund’s rule

Answer 9

1. fill lowest energy orbitals first
2. only 2 electrons in an orbital and they are spin paired
3. each orbital of degenerate eneryu is first filled with only one electron before they are paired

Question 10

Draw out the hybridzations

SP, SP2, SP3 hybrids and their characters

Answer 10

1. 50%:50%
2. 33%s:67%p
3. 25%s:75%p