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Flashcards in bonding Deck (17)
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1

carbocations

carbon with a +1 formal charge can make 3 bonds total

2

formal charge vs oxidation state

both are bookkeeping methods for electrons. Formal charge assumes that the compound is 100% covalent. Oxidation state assumes it is 100% ionic

3

carbanions

carbon with a -1 formal charge can make up to 3 bonds and must have a lone pair.

4

pKa values

the higher the value the weaker the acid

5

Ka values

the higher the value the stronger the acid

6

how is Keq related to pKa

Keq = pKa(left) - pKa(right)
the reaction always favors the weaker acid

7

predicting the stability of a conjugate base

there are two main factors
1.the electronegativity... as we increase electronegativity the better the base becomes at stabilizing electrons
2.the size... the bigger the base the better it would be at spreading out the electrons thereby getting less repulsion.
3.induction: if you have more electronegative atoms in a compound which would be able to help spread a negative charge around the compound
4.resonance
5.hybridization: the more S character you have the smaller the distance between the electrons and the nucleus therefore losing a H+ would be more favored. Making SP hybirds the most acidic and SP3 the least

8

nitrogen formal charge of 0
+1
-1

3 bonds with a lone pair
4 bonds no lone pairs
2 bonds 2 lone pairs

9

oxygen formal charge
0
+1
-1

2 bonds 2 lone pairs
3 bonds 1 lone pair
1 bond 3 lone pairs

10

patterns for resonance structures

1.a lone pair next to a pi bond
2.positive charge next to a pi bond
3.strong electronegatihain with only single bondsvity difference

11

alkanes

a carbon chain with only single bonds in the main chain

12

alkyl

any branches

13

staggered vs eclipsed projections

peace sign in front for both. For staggered fill in the spots in between. For eclipsed directly behind.

14

dihydral angle (DA)

the distance between the H atoms in a staggered projections. To illustrate how staggered it is

15

what is a gauche interaction

its a newman projection which two methyl groups are next to each other causing an energy loss of 3.8 KJ/mol per pair. if there are 4 CH3 groups right next to each other then there are 3 pairs.

16

axial vs equatorial

axial hydrogens are not parallel to any other atom. Equatorial atoms are parallel to atleast one other.

17

bond strain

an increase in energy associate with bond angles that deviate from the ideal of 109.5