bonding and intermolecular forces

Question 1

formal charge formula and rule

Answer 1

FC = valence elections - 1/2B - L

B = bonding electrons
L = number of lone paired electrons 

the better formal charge minimizes magnitude of charges

Question 2

resonance structures

Answer 2

where nonbonding electrons, and double/triple bonds may move around

Question 3

bond dissociation energy

Answer 3

energy required to break a bond homolytically

Question 4

homolytic vs heterolytic bond cleavage

Answer 4

homolytic - one electron of the bond being broken goes to each fragment of the molecule, forming two radicals
heterolytic - both electrons of the electron pair that make up the bond end up in the sam atom, forming both a cation and an anion

Question 5

how does bond order (number of bonds) correlate to bond length and strength

Answer 5

more bonds = shorter bonds and higher bond strength

Question 6

how does s and p character affect bond length

Answer 6

greater s percentage causes a shorter bond

Question 7

covalent bonds

Answer 7

formed between atoms when each contributes one or more of its unpaired valence electrons

Question 8

polar vs non polar

Answer 8

polar - uneven electron density

non polar - even electron density

Question 9

Lewis base

Answer 9

electron donator, ligand, and nucleophile

Question 10

Lewis acid

Answer 10

electron acceptor

Question 11

ionic bonds

Answer 11

when an atom gives its valence electron to another atom to form a cation and an anion

Question 12

types of molecular geometry if zero lone pairs present

Answer 12

linear, trigonal pyramidal, tetrahedral

Question 13

types of molecular geometry if one lone pair present

Answer 13

bent, trigonal pyramid

Question 14

types of molecular geometry if two lone pairs present

Answer 14

bent

Question 15

number of electron groups and hybridization

Answer 15

2 electron groups = sp
3 electron groups = sp2
4 electron groups = sp3

Question 16

sigma and pi bonds

Answer 16

sigma - consists of two electrons localized between two nuclei, formed by end to end overlap of one hybridized orbital) (ex. a bond between CH in ethane is sp3-s)

pi bond - formed by the proper parallel side to side alignment of two unhybridized p orbitals on adjacent atoms

Question 17

what types of bonds in a single, double, and triple bond

Answer 17

single - 1 sigma
double - 1 sigma, 1 pi
triple - 1 sigma 2 pi

Question 18

What causes a molecular to be non polar

Answer 18

a molecule containing two or more symmetrically oriented polar bonds, canceling out the bond dipoles

Question 19

types of IMFs

Answer 19

ion-dipole, dipole-dipole, dipole induced dipole, LDF, hydrogen bonding (strongest type)

Question 20

result of strong intermolecular forcers

Answer 20

greater melting point, greater boiling point, greater visocities, and lower vapor pressures

Question 21

hydrogen bonding requirements

Answer 21

1. a molecule must have a covalent bond between H and either N,O or F
2. another molecule must have a lone pair of electrons on an N, O, or F atom

Question 22

vapor pressure

Answer 22

pressure exerted by the gaseous phase of a liquid that evaporated from the exposed surface of the liquid, increases with weaker IMFs and temperature

Question 23

types of solids

Answer 23

ionic (strong), network (covalent bonds, strong), metallic (strong), molecular (weak)