Water Flashcards
Structure of water
1 atom of oxygen + 2 atoms of hydrogen
What type of bonds are in a water molecule
Covalent
What charge does the oxygen atom have in water
What charge does the hydrogen atom have in water
Negative
Positive (both)
Because the charges in water are opposite what type of molecule is it
Polar molecule
What are the forces of attraction between different water molecules called + strength
Hydrogen bonds
Weak but have a large number so large effect on the properties
Properties of water x4
- high specific heat capacity
- high latent heat of vapourisation
- great solvent
- good in metabolic reactions
Why is water good habitat for aquatic organisms to do with specific heat capacity
- very high specific heat capacity
- the energy put in goes to breaking hydrogen bonds rather than increasing kinetic energy of water molecules
- water acts as a buffer to rapid temperature change
- if the temperature changed to rapidly organisms would not function properly
Is ice more or less dense then water
Properties of ice
Ice is less dense so it floats
Insulate water below stops it freezing - organisms can continue living
Benefit of water having a high specific lanterns heat
Organisms can cool without losing a great deal of water
Eg. Sweating
Because water is such a good solvent what can it be used as + example
Transport substances
Eg. Blood plasma
Transport in xylem
Eg. Mineral ions
What is water molecules sticking together called + why do they do this
Cohesion
Due to hydrogen bonds
Why is cohesion of water a benefit in xylem
Allows long columns of water to travel in xylem tubes
Benefit of cohesion on eg ponds
Cohesion causes surface tension where water meets air
This allows it to act as a habitat
Example of reactions water is used for
Hydrolysis
Photosynthesis
Where is water produced which reactions
Condensation reactions
Aerobic respiration
Water is a ….. solvent
Good
What has a relatively.,.. specific heat capacity
High
Water has relatively …. Latent heat of vaporisation
high
Water is ….. dense when solid
Less
Water has …. surface tension and c…
high
Cohesion
What are the key properties of water that make it essential to living organisms x5
As a solvent allowing the transport of substances
High specific heat capacity so buffers changes in temperature
Large latent heat of vaporisation so provides cooling effect
Cohesion so produces surface tension for small organisms
Cohesion so imports columns of water
When is water used in metabolism + what does the water do x2
Hydrolysis molecule of water breaks bond
Condensation releases water molecule
Explain why water is a good solvent
Water is polar
Ions will be attracted to the opposite charges
Ions will be surrounded by water molecules
Why does water have a high latent heat of vaporisation + why is this beneficial
Lots of energy required to break hydrogen bonds
Evaporation of sweat cools down the body.
Why does water have a specific heat capacity
Lots of heat used to break hydrogen bonds so less heat to actually increase the temperature
Why is it important water has a specific heat capacity
Acts as a buffer prevent temperature changes
Cohesion is between
Water molecules
Adhesion is between
Water and other molecules
Benefits of water cohesion
Supports columns of water in tube - like transport e.g. xylem
Strong surface tension when it meets air
