Water properties Flashcards
Why is water polar?
The shared electrons are slightly more attracted to the oxygen, so it is slightly negative but the hydrogen atoms are further away from the electrons so they are slightly positive, making water a polar molecule
Why does water have hydrogen bonds?
The positive hydrogen region is bonded by electrostatic attraction to the negative oxygen region, making hydrogen bonds
Why does water have surface tension and cohesion?
Water has surface tension because the water molecules on the top of the water is H bonded with those beneath it, so the surface water molecules are more connected to the lower water molecules than the air, so it has the ability to resist a force that is applied to it(surface tension)
Water has cohesion because of the H bonds that bring the molecules together.
Why is water having surface tension and cohesion important?
- So that animals can walk over water
- So that water can go up the xylem through the roots because of cohesion and adhesion.
Why does water have a high specific heat capacity?
More energy is needed to heat up water, because of the many H bonds that make it stronger as they are harder to overcome
Why is water having a high specific heat capacity important?
- It means that living things, including prokaryotes and eukaryotes, can live in at a stable temperature for enzyme-controlled reactions to happen properly
- It gives aquatic life a stable environment to live in
Why is ice less dense than water?
Water freezes normally until 4 degrees where the molecules make an arrangement which is slightly less dense than in water because it is polar, so it is more spread out than water, making it less dense.
Why is ice being less dense than water important?
- Ice floats so in bodies of water there is a layer on top , so the aquatic life can stay insulated from the cold in winter
- Aquatic animals can have a stable environment throughout winter
- also if it was denser the pond would completely freeze in the winter killing lilfe
Why does water have a high latent heat of vapourisation?
More energy is needed to break both the covalent bonds and the H bonds, which there are a lot of.
Why is water having a high latent heat of vapourisation important?
- It is helpful when animals sweat, because it can vaporise, cooling them down
- Plants also cool when water is released from the mesophyll cells
Why is water being polar important?
-It can transport ions and molecules in the blood separately(as the ions not as the molecule/whole structure) and can help in reactions to break down substances
Why is water being a reactant important?
-It can help in enzyme reactions and also in hydrolysis of large biological molecules such as carbohydrate, proteins and lipids
It is also helpful in the photosynthesis reaction
Why is water being a liquid important?
- Provides a habitat from aquatic animals
- It forms a major component of living tissues
- Provide a reaction medium for a chemical reaction
- Provides an effective transport medium
Why is water being a good solvent important?
- It can be used as a way of transporting ions, molecules and dissolved ions and molecules
- It is useful in the cytoplasm, which is 70% water, because most reactions work better with smaller molecules
