Water and its functions

Question 1

What is water made up of

Answer 1

Hydrogen and oxygen

Question 2

Charges in water molecule

Answer 2

Oxygen partially negative
Hydrogen partially positive
Dipolar molecule

Question 3

Bonding in water

Answer 3

Different poles attract forming hydrogen bonds that help water molecules stick together

Question 4

Specific heat capacity of water

Answer 4

Water molecules stick together so requires more energy to separate them than with H2 bonding
Higher boiling point otherwise water would be a gas at room temp

Question 5

Latent heat of vaporisation definition

Answer 5

Hydrogen bonding between water molecules means it requires a lot of energy to evaporate 1 gram of water

Question 6

Cohesion and surface tension in water

Answer 6

Tendency of molecules to stick together
With hydrogen bonding = water has large cohesive forces and these allow it to be pulled through a tube (xylem vessel)
Force called surface tension and mean that the water surface stays together

Question 7

Water in metabolism

Answer 7

Water used to break down molecules using hydrolysis, water produced in condensation reactions
Chemical reactions take place in aqueous medium
Photosynthesis

Question 8

Water as a solvent

Answer 8

Gases = O2 and CO2
Wastes = ammonia and urea
Inorganic and small hydrophilic molecules = amino acids, monosaccharides and ATP
Enzymes = reactions

Question 9

Other important features

Answer 9

Evaporation = control temp in organisms
Not easily compressed = provides support
Transparent = aquatic plants can still photosynthesis