Chapter 1 Flashcards
covalent bond
- when 2 atoms share a pair of electrons
- strongest of all bonds
- 2 kinds:
non-polar covalent
polar covalent
non-polar covalent bonds
2 atoms with same or similar electronegativity share electrons equally
polar covalent bond
when 2 atoms share electrons UNequally
ionic bonds
2nd strongest bond
- electronegativity of one atom is greater than that of the adjoining atom
- the one with higher electronegativity pulls electrons to its valence shell -> becomes an anion (negatively charged)
H-bonding
hydrogen covalently attached to one electronegative atom is attracted to another electronegative atom
- similar to ionic bonds
- stronger than van der Waals interaction & hydrophobic interactions
- ex. attraction between H-bonds between H2O and NH3 & the H-bonds of DNA, RNA &; proteins
Hydroxyl
-OH
alcohol
easily soluble in water
polar
Carbonyl
-C=O –> aldehyde
If C is in the middle –> ketone
slightly polar
Carboxyl
–COOH
acid - will ionize to form -COO and H+ to increase [H+] of the solution
polar
Amino group
-NH2
base - can pick up an H+ (H+ –> -NH3)
Phosphate
-OPO32-
acid - can give 2 H+ (increase acidity of solution)
highly polar
Sulfhydryl
-SH
thiol
Methyl
-CH3
hydrocarbon
non-polar
list functional groups based on polarity from most polar to most non-polar.
- phosphate
- carboxyl
- amine
- hydroxyl
- carbonyl
- sulfhydryl
- methyl
which functional groups are acids?
carboxyl
phosphate
which functional group is a base?
amine
