Water Flashcards
What is the importance of water?
-Is a metabolite (used in many reactions).
-Cells are mostly water.
-Metabolic reactions in cells happen in an aqueous solution.
-Most common compound
-Properties result in the molecules ‘sticking together’.
What is the structure of a water molocule?
-Oxygen is covalently bonded to two hydrogens (shares a pair of electrons).
-Hydrogen is positively charged, oxygen is negatively charged.
-Contains hydrogen bonds between water molecules.
-Very stable structure.
What makes water a dipolar molocule?
Has two differently charged regions.
Why is water used as a solvent?
-Because of it polarity substances can dissolve and reactions can take place in it.
-Transport medium (transported)
-Toxic substances can be diluted
What substances can dissolve in water?
-Has to be polar/ hydrophilic.
What is cohesion between molocules?
-At an air-water surface the cohesion between water molecules produces surface tension.
Why is cohesion between water molecules important?
-Can lead to a solid like surface which explains why some animals can walk on the surface.
-Explains water columns and how they do not break which is needed for transpiration.
What is surface tension?
-Attraction between water molecules creates tension and produces a delicate membrane.
-Lets some invertebrates live on water.
What his high latent heat of vaporisation?
-A lot of energy is required to turn water from a liquid to a gas.
-When water evaporates a lot of energy is lost.
What is high specific heat capacity?
-A lot of energy is required to raise the temperature of water.
Why is high specific heat capacity useful?
-Water is thermally stable so the temperature of the sea does not change much.
-Provides a stable environment for living organisms under the sea.
What is the density of water?
-Waters optimal density is 4 degrees and ice has a lower density so it floats.
Why is the density of water important?
For animals who live in artic environments, floating on ice is how they transport.
-Water underneath ice will not freeze.
What are some other important features of water?
-Water is transparent so underwater plants can photosynthesise.
-Cohesion allows for transpiration to happen.
