Water Flashcards
What are the properties of water?
It is a reactant, a solvent, a transport medium, a habitat, a coolant and a lubricant
What is the function of water as a reactant?
It is involved in many important chemical reactions such as photosynthesis uses water as a raw material for the synthesis of carbohydrates and hydrolysis uses water molecules to break down molecules.
What is the function of water as a solvent?
Polar molecules and ions (as they are charged molecules) dissolve in it and water molecules cluster around the solute keeping them apart, and most biological reactions occur in solution, for example, in the cytoplasm of a cell
What is the function of water as a transport medium?
It is a liquid over a range of temperatures and a solvent so it can easily transport, for example, blood cells, nutrients and gases are transported in water in the veins and arteries and nutrients are transported in the water in xylem vessels.
What is the function of water as a coolant
It helps with temperature control as it has a high specific heat capacity and high latent heat of evaporation
What is the function of water as a habitat?
As it helps with temperature control, is a solvent and becomes less dense when it freezes means many organisms can survive and reproduce in it
How is water a lubricant?
Synovial fluid (mainly water) prevents bones from scraping against each other and organs are largely surrounded in fluid that allows them to move against each other without damage.
Why is oxygen a electronegative?
It has a tendency to attract pairs of electrons
Why is water a polar molecule?
The molecule has no overall charge but the negative electrons are unevenly distributed because the oxygen draws them away from the hydrogen atom. This means the oxygen atom has a slightly negative charge and the hydrogen atom has a slight positive charge
What is the cause for hydrogen bonds?
The positive pole of one water molecule is attracted to the negative pole of another water molecule and the attractive force is a hydrogen bond
What is cohesion?
When water molecules attract each other and stick together, forming hydrogen bonds
What is adhesion?
When water molecules stick to other surfaces by forming hydrogen bonds with other molecules or ions
How does surface tension work
The hydrogen bonds are very weak however they constantly breaking and reforming and water molecules on the surface have nothing to be attracted to, so they are pulled down by the molecules beneath them. Also, in a container, adhesion causes water molecules to stick to the sides of the container instead of overflowing and the surface tension made is string enough to support small organisms such as pond skaters
Why does water have a high specific heat capacity?
The hydrogen bonds between molecules can absorb a lot of energy so a lot of energy is needed to heat water up,so water has a high specific heat capacity
What is the function of water having a high specific heat capacity?
Water does not experience rapid temperature change, making it a good habitat as the temperature under the water is more stable than on land
