Describe the structure of the water molecule and indicate how this structure is responsible for many of the unique properties of this vital compound.

1) Water is a polar solvent due to difference in the electronegative values between the hydrogen and oxygen which sees the Oxygen end of the molecule having a slightly negative charge while the hydrogen end has a slightly positive charge.  This allows water to dissociate to form positive and negative ions.
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Because water is able to form positive and negative ions in solution and as such it is able to dissolve compounds because the negative and positive ions it possesses break the bonds of compounds and keep them apart.   This is why it is a Universal Solvent and why it can dissolve solutes in the blood, be a medium of transport in plants, make  up a large percent of cell cytoplasm and aid in aquatic environment survival.

2) Water because of its dipole is able to form hydrogen bonds which is where a highly electronegative atom in a molecule with a lone pair of electrons in this case the oxygen in water bonds with the hydrogen of another molecule.  
   a) this allows water to have a high specific heat capacity which means            that a lot of heat energy is needed to change water by 1°C.  This is            because much energy is needed to break the hydrogen bonds in                water.  This allows water to maintain body temperature by absorbing          energy in the form of heat in the body with there only being an                    incremental change in the temperature of the body.
  b) Because of the hydrogen bonding between water molecules, water             also possesses a high heat of vaporization which means that much           energy is needed to convert 1kg of water from its liquid state to its             gaseous state.  With this being the case, water can act as a coolant by       absorbing the heat from a body an remove it when it evaporates as it         is in the case of sweat.
  c) The hydrogen bonds also allow water at the surface to contract so that        it occupies the least possible area.  This sees where water forms a            thin layer atop a water body.  This allows for some objects to float              atop the water and also allow some small animals to move across the        surface of water often as an escape from predators.  
       Water also has a high cohesive and adhesive power and this                      attraction is more powerful than gravity.  This allows water to move            through capillaries and up xylem vessels in plants. 

The answer is c) pyrite