important functions of water
- biochemical reactions require an aqueous environment
- water is an important means of transport
- reluctant to temperature change (acts as a temperature buffer in organisms and ecosystems)
what bonds hold water together?
covalent bonds (sharing electrons)
which is more electronegative oxygen or hydrogen?
oxygen
water causes what charges?
partial
what type of covalent bonds does water have?
polar
hydrogen bonds:
the attraction between partially positive hydrogen and an atom with a partially negative charge from a different molecule
one water molecule can form
4 hydrogen bonds
hydrogen bonding allows water to be
- liquid at room temperature
- solid at cold temperature
- gas at hot temperature
hydrophilic:
water-loving
hydrophobic:
water-fearing
these molecules are insoluble in water
nonpolar
these molecules are soluble in water
polar and ionic
acid (bronsted-lowry):
donates protons into the solution (H+)
base (bronsted-lowry):
accepts protons//takes protons out of solution (H+)
pH scale:
the negative log of H+ concentration in solution
pH= 0
very acidic
pH = 7
- neutral
- [H+] = [OH]
pH = 14
very basic
pH<7.0
- acidic
- [H+] > [OH]
pH>7.0
- basic
- [H+] < [OH]
proton:
10^0
10^-7
10^-14
pH val.
0
7
14
a 1 unit change =
10 fold change in concentration
the lower the pH
the higher the hydrogen ion
the higher the pH
the lower the hydrogen ion
