What are the properties that are important for water
- Metabolite
- Solvent
- High specific heat capacity
- Large latent heat of vapourization
- Strong Cohesion
What is a solvent and why is it a property of water
A solvent can dissolve other substances, water is a solvent because of its polarity, its charge, hydrophilic
What percentage of water is found in the body?
70%
Why is water described as a metabolite
It is involved in many metabolic reactions including condensation and hydrolysis reactions, photosynthesis and respiration
Define specific heat capacity
The amount of energy required to raise 1g of water by 1C
What is the importance of water having a high specific heat capacity?
Water acts to moderate temperature changes, acting as a buffer against sudden variations in temperature which would harm both aquatic and land organisms
Where does reactions take place?
In the cytoplasm
Describe the structure of water
- Polar
- Due to the distribution of electrons
- As water molecules are polar, they form HYDROGEN BONDS with other water molecules making them cohesive (stick together)
- This is why water is a liquid
What kind of bonds are found in water molecules?
Covalent bonds
What pairs are found in oxygen
Lone pairs
What is the strength of the hydrogen bonds?
Relatively weak
What is released from the body to regulate body temperature?
Sweat
What is required to break the hydrogen bonds in water and how does this affect the temperature required?
Energy is required to break the hydrogen bonds in water, so it requires lots of energy e.g. 100C to boil
What is adhesion?
Water molecules sticking to other materials e.g. glass
What is the importance of the latent heat of vaporization in water?
- It provides cooling by evaporation
- Because energy is required to break the HYDROGEN BONDS, a lot of energy is required for evaporation
- This makes cooling an effective method
What is the importance of the strong cohesion in water molecules?
- Supports columns of water in plants
- ## Produces surface tension supporting small organisms and allowing them to stay afloat
Why can water molecules be pulled up a narrow tube?
- Because molecules stick together (cohesion)
Give an importance of ice floating
so, it maintains aquatic habitat beneath
Why is water transparent?
It allows light to penetrate for photosynthesis
Who is waters enemy and why?
Lipids because they are hydrophobic due to their non-polarity
Where does water enter plants?
Via earth roots
