water Flashcards
what is chemical structure of ice
each water molecule is H bonded to four other water molecules to form a tetrahedral arrangement.
why is ice less dense than water
open hexagonal lattice structure.
what happens to ice as it melts
its 3D tetrahedral structure breaks down as thermal motion disrupts, distorts and breaks up the H bonded lattice
Is bulk water static
no
why is there more hydrogen bonds per water molecule in liquid that in ice
bulk water is a seething mass of water molecules in which H bonded clusters are continually forming breaking and re forming.
why does water have a stronger boiling point compared to similar molecules
ammonia and HF and hydrogen sulfide have weal inter molecular forces.
So high b.p is due to both strength and large number of H bonds formed from each molecule
why does water have a high melting point than other hybrids
Need to break the H bonds to melt ice. Only get a small change in volume so melting point only occurs if there sufficient entropy change, but liquid water has low entropy.
why does water have high surface tension
water molecules at interface have fewer hydrogen bonds so feel a net attractive force.
does water have a high specific heat capacity
yes
why does ice melt at higher pressure
normally high pressures cause freezing as solids are more ordered. but the gradient is negative for water.
what does P&G water purification contain
bleach (hypochlorate), Oxidant, coagulant, anionic polyacrylamide, betonite clay particles
How does the P&G water purification work
bleach and oxidant kill bacteria and parasites
coagulant and anionic polyacrylamide and clay cause aggregation of particulates.
removes heavy metals, dying bacteria and clarifies water.
