The chemistry of water Flashcards
what are the 4 emergent properties of water?
the cohesion of water molecules
temperature moderation by water
the floating of ice on liquid water
water is the solvent of life
what is the cohesion of water?
the ability of water to travel through plants against gravity
water is more structured due to H bonds
high surface tension due to H bonds
how does water moderate temperature?
Water has a high specific heat
Evaporative cooling regulating earths temperatures
what does it mean for water to have a high specific heat?
it can absorb high levels of heat and resist temperature change (due to H bonds)
why does ice float?
the H bonding forms a crystalline lattice making ice less dense than water.
why is floating ice important to the wider planet?
water bodies would freeze from the bottom up harming plants and later the wider ecosystem
floating ice insulates water in winter preventing it all from freezing.
ice sheets provide a habitat at the poles
why is water the ‘solvent of life’?
its a good solvent due to its polarity, the charge attractions allow water to separate ions and surround them - making a solution
how do non-ionic solutions dissolve in water?
water molecules form H bonds with them
t/f can substances be hydrophilic without dissolving?
true
what makes substances hydrophobic?
non-ionic, non-polar
are cell membranes hydrophilic or hydrophobic?
hydrophobic- don’t dissolve, allowing them to encapsulate essential compounds
how does water disassociate?
when a hydrogen atom involved in a water bond shifts from one molecule to another
why would H+ and OH- ions have drastic affects in molecules
they are highly reactive
(H+)(OH-)=
10^-14
pH =
-log10(H+)
