1.7: Water

Question 1

Describe the structure of water

Answer 1

• Dipolar molecule
• Uneven distribution of charge
• Oxygen partially negative and hydrogen is partially positive

Question 2

What are the 5 properties of water?

Answer 2

1) Metabolite e.g in condensation and hydrolysis reactions
2) Solvent in metabolic reactions
3) High specific heat capacity, buffering changes in temperature
4) Large latent heat of vaporisation, providing a cooling effect with loss of water through evaporation
5) String cohesion between water molecules, supporting columns of water and providing surface tension

Question 3

Why is water a good solvent?

Answer 3

Charged molecules can dissolve in it as it is dipolar.

Question 4

Why does water have a high specific heat capacity?

Answer 4

Requires a lot of heat energy to heat due to high amount of hydrogen bonds. Useful as the temperature of water remain stable if surrounding temperature fluctuates so organisms can always have their optimum temperature to work.

Question 5

Why does water have a large latent heat of vaporisation?

Answer 5

Requires a lot of energy to convert water into gas due to hydrogen bonds. Advantageous as provides cooling effect when sweating.