Water Flashcards
What shape are water molecules?
V shaped
Why are water molecules v shaped?
The two lone pairs of electrons maximise distance between themselves
What word describes what oxygen is because of the fact that water has more protons so it is pulling the electrons of hydrogen towards itself?
Electronegative
What are the charges on water?
Oxygen is slightly negative and hydrogen is slightly positive so the electrons are slightly nearer oxygen
What does water have due to the uneven distribution of charge and what property does this give it?
Water has a permanent dipole so it is polar
What bonds does water form with other molecules
Hydrogen bonds
How strong are hydrogen bonds and how much effect do they have on water?
They are very weak but due to them being in large numbers they have a large effect on water
What do the hydrogen bonds create?
Cohesion
What does cohesion do?
Supports the columns of water in plants xylem so water moves through the xylem vessel through cohesive and adhesive forces
What does cohesion between the molecules produce?
Surface tension when water meets the air which supports pond skaters
Can you fit more drops of water on a coin than ethanol and why can you?
Yes sue to cohesion so water is not as wet as ethanol
What are ions or polar molecules that are attracted to water called?
Hydrophillic molecules
What are molecules that repel water called?
Hydrophobic molecules
What type of reaction is it when water molecules break up large molecules into smaller molecules eg photosynthesis?
Hydrolysis reaction
What type of reaction is it when a water molecule is released when chemical bonds are formed between small molecules to make a large molecule eg respiration?
Condensation reaction
What thermal property does water have which makes it thermostable?
High specific heat capacity lots of energy required to raise temperature
What thermal property of water provides a cooling effect?
Large latent heat of vaporisation due to it taking a lot of heat to break the hydrogen bonds
What happens as water freezes?
It expands creating ice which floats and insulates the water below so it doesnt freeze allowing aquatic life to survive under ice
What thermal property allows water to provide support and buoyancy?
High density
Why is it useful that water is transparent?
It allows light to travel through it allowing aquatic plants and algae to photosynthesise
What is water used as in the blood and in plant xylems
Transport medium
What word describes the fact that water is involved in many chemical reactions?
It is a metabolite
