Ch. 3 Water Flashcards
big idea: properties of water, as well as pH, and buffers (bicarbonate)
what is the molecular structure of a water molecule?
two hydrogen molecules polar covalently bound to an oxygen molecule
hydrogen atoms can form hydrogen bonds with other nearby molecules
what is cohesion and why is it relevant?
cohesion = water bound to water
- creates surface tension, the strength of a surface of a liquid
-allows plants to pull water molecules up their roots
what is adhesion and why is it relevant?
adhesion = water bound to other molecules
-allows water to stick to plants and acts as lubrication and cushioning for organs
what is specific heat and what is waters?
-specific heat = energy required to raise 1g of liquid by 1 degree celsius
water’s = 4.18 J / g C or 4.18 J / gK
what is heat of vaporization?
the quantity of heat required to vaporize 1g of liquid
-waters is very high, so we can sweat and cool ourselves down
what is the densest form of water?
-liquid water:
ice water is less dense = why it floats on the surface and keeps all the underwater organisms alive and not dead
why is water relevant as a solvent?
-water is a great solvent due to its POLARITY - many things dissolve in it
solution = solvent + solute
in an aqueous solution, water is the solvent
what are hydrophillic & phobic compounds?
hydrophilic = likes water, wants to mix in and be dissolved by it, many polar bonds
hydrophobic = hates water, will not mix or dissolve in it, think oil, many noncovalent bonds
what are the other “forms” of water?
OH- = hydroxide
H+ = proton
what is an acid and base?
acid = compound that donates a H+ proton
base = compound that accepts a H+ proton
what are buffers?
compounds that resist changes in pH by absorbing excess h+ or donating h+ when levels are too low
made of acid base pairs such as the BICARBONATE BUFFER SYSTEM!!!
what is the bicarbonate buffer system equation?
Co2 + H2O <–> H2CO3 <–> HCO3- + H+
