BCHM 3050: 2.1 Water Molecules and Hydrogen Bonds

human body comp breakdown

• 40% intracellular water

• 40% non-water

• 15% extracellular water

• 5% water in circulatory

water has a ____ shape

tetrahedral, if you include the oxygen’s unpaired valence electrons

oxygen is ____ electronegative than hydrogen

more; water has a bent geometry and uneven charge distribution

• makes it an effective polar solvent

because opposite charges attract…

neighboring water molecules orient so that opposite partial charges align

• allows for up to 4 hydrogen bonds to establish and unique water characteristics

electronegativity:

measure of an atom’s affinity for electrons

H-bonds:

depend on partial charges that attract and intermediate bond length

hydroxyl groups and amine groups…

are key players in hydrogen bonding in biomolecules

H donors:

N-H and O-H groups

H acceptors:

N, O, S

covalent bonds:

depend on shared electrons and shortest bond length

• these bonds are key for the structure of biomolecules

no bonding means…

distance btwn atoms is too far

non-covalent bonds are weak, but important for…

stabilizing 3D structure, molecular interactions, and they are stronger in numbers