Water Revision Carousel Flashcards
What allows water molecules to have cohesive and adhesive properties?
Hydrogen bonds
Explain the polar nature of water.
-O is more electronegative than H/ unequal share of e- / e- spend more time orbiting around O than H
-Gives regions of slight positive and negative
Water molecules stick together because of the many hydrogen bonds that form between molecules of water. What is the name of this property of water?
Cohesion
Why is a stable water temperature (due to high specific heat capacity of water) good for cells?
Enzymes will denature if too hot and reactions will slow if too cold
Why is water adhesive?
Due to its polar nature meaning that it’s attracted to other substances, sticking to them
Why can water act as a medium for chemical reactions?
Because it’s polar and will dissolve polar molecules easily. Many reactants in living cells are polar in nature
Why is water cohesive?
The many hydrogen bonds between water molecule make them stick together
Why is ice less dense than liquid water?
Below 4 degrees the formation of hydrogen bonds will cause water to form a fixed lattice keeping the molecules further apart on average than they are in a liquids where hydrogen bonds are breaking and reforming as molecules move past each other
Why is ice floating a benefit for aquatic organisms?
-They are still able to move about under the ice as is their food.
-The layer of ice insulates the water below, keeping it liquid for longer
Why is water a good coolant?
-As it has a high specific heat capacity and can act as a heat sink.
-A lot of energy is transferred when water evaporates from a surface, cooling it
What kind of bonds are formed between H and O atoms in different water molecules?
Hydrogen bonds
Why does water have a higher boiling point than Carbon Dioxide?
The many hydrogen bonds between water molecule means that is takes a lot of energy to increase the temperature of water to become gaseous
What causes surface tension?
Water molecules are cohesive and are attracted to one another more strongly than they are to air
List the key properties of water that are valuable for living organisms.
-Good solvent
-High specific heat capacity
-High latent heat of vaporisation
-Less dense as ice
-Polar
Water molecules are attracted to other substances making them wet. What is the name of this property of water?
Adhesion
