water-bio mols Flashcards
In water, 1)oxygen and 2)hydrogen are…3)making it…4)these are called
1) partially negatively charged
2) partially positively charged
3) dipolar
4) hydrogen bonds
hydrogen bonds are1)…unless…2)
1) relatively weak
2) unless theres lots of n them working together-like in water
properties of water
1)density
2)metabolite
3)universal solvent
4)high SHC
5)high LHV
6)surface tension, cohesion, adhesion
density (why does ice float?)
1)water freezes into a lattice
2)water expands so is less dense so floats
3)this forms an insulating layer as a barrier to cold
4)water below remains liquid so living things can live
metabolite
1)water is in the medium which enzyme-catalysed reactions can occur
2)metabolic reactions occur faster in solution
3)used in hydrolysis, condensation and photosynthetic reactions
uni solvent
1)metabolic reactions occur faster in solvents
2)water dissolves more substances than any other liquid due to polar nature
3)ionic bonding can take place in water (dissolving)
cohesion
water sticks to water due to hydrogen bonds
adhesion
water sticks to other things due to hydrogen bonds
surface tension
1) how hard it is to break the surface of water
2)water forms H bonds w molecules below it, but not w air above it
3)this causes a tough film due to cohesion forces
high SHC
1)has thermal stability due to this
2)water needs lots of heat energy to raise the temp of it by a certain amt
3)bc the H bonds need lots of energy to break as they’re strong together
4)means water is a buffer for sudden temp changes
high LHV
1)water needs lots of energy to evaporate turning to gas
2)due to lots of strong H bonds together
3)cooling
high LHV in terms of sweating
1)sweat secreted when body temp is too high
2) water in sweat gains energy so can break free from bonds holding it together
3)can turn into water vapour (evap)
4)takes heat energy with it as it evaps
