Some homework questions that i got wrong

[nemzy]

question 1:

which property of water is most important for the functioning of organism at molecular level?

i put A) Cohesion and high surface tension, but it was wrong

the other choices were high specific heat, high heat of vaporation, expansion upon freezing, and versality of solvent

could it be high heat of vaporation? for example, without that we wouldn't have evaporative cooling, and we could die from heat?

question 2:

wat causes clouds to cause rain to fall?

i put: cloud absorbed sunlight, which provided the energy to condense the vapor to water..i thought this was right?

thanks

 

[nautica]

We can rule out expansion, upon freezing b/c that is a bad thing. We can rule out high heat of vaporization b/c most animals never get close to 100 C. I don't know if we can rule out high specfic heat b/c it does have that but I am not sure why that would be important. You said the surface tension was wrong. So that leaves me with veritility of solvent.

Nautica

 

[Monique]

1. Water has a very high dielectric constant, that makes it a very good solvent for a wide range of molecules.

2. When air is over-saturated with water, rain droplets will form. When airpressure drops, a cloud will start raining because this will lead to over-saturation. Things that can cause this is for instance rapidly rising warm air (in higher atmospheres the airpressure is low).