module 2 - 3.2 water Flashcards
what does high content of water in cells and tissues help with?
helps them to maintain a constant temperature
how does water help to maintain constant temperature in cells and tissues?
it acts as a temperature buffer
how are the properties of water formed?
due to hydrogen bonding between 2 molecules
why is it important for water to have a high specific heat capacity?
crucial for living organisms that need to maintain temperature
what is does it mean when water has a high specific heat capacity?
it takes a lot of energy to raise the temperature of water
what happens to enzymes if specific heat capacity is too high?
denature if temperature too high and therefore can’t bond with active site
what is the density like for H2O?
less dense as a solid than a liquid
what is the angle between 2 hydrogen bonds connected by the oxygen molecule?
104.5 degrees
what is water made up of?
- 2 positively charged hydrogen atoms (beta plus)
- 1 negatively charged oxygen atom (beta minus)
why is water a polar molecule?
it has both positively and negatively charged areas, but it has 2 charged regions, it is dipolar
how far away are the hydrogen atoms from the center of the oxygen atom?
approximately 0.09nm
what is the boiling point of water?
100 °C
what is the strength of a hydrogen bond compared to multiple hydrogen bonds?
one bond - very weak
multiple bonds - strong
what type of compound is water?
molecular compound
which reactions is water a metabolite?
- hydrolysis reactions - splitting in the presence of water
- condensation reactions - forming/ making water
adjacent water molecules are attached due to what?
due to waters polarity (uneven distribution of charges)
how are adjacent water molecules attached?
the slight positive charge of a hydrogen atom of one molecule is attracted to the slight negative charge of an adjacent oxygen atom
water is very cohesive, what is meant by this?
tendency for water molecules to form weak bonds and stick to each other
why do water molecules spread out/ expand?
to accommodate more bond formation
why does ice float?
because water freezes from the top down
ice is lighter than water/ less dense than water
what do large molecules do in water?
they do not dissociate in water as they have large intermolecular forces
polar substances which dissociate in water are said to be what?
hydrophilic
what is sodium chloride (salt) made up of?
positively charged sodium ion and negatively charged chloride ion
(opposite charges cause 2 ions to attracts and causes a bond to form)
which molecules and compounds dissociate in water?
water molecules and ionic compounds
