2.4 - Water Flashcards
The structure of water Hydrogen bonding in water The role of water in living organisms How the properties of water relate to its function
What type of bonds hold the atoms in a water molecule together?
Covalent bonds
What type of molecule is water?
Dipolar
Why is water a dipolar molecule?
It has slightly positive and negative poles
What type of bonds form between water molecules?
Hydrogen bonds
What are some roles of water in living organisms?
Solvent
Why is water known as the universal solvent?
It dissolves more substances than any other liquid
Why is water a good solvent for ionic compounds?
Its polar molecules surround and separate ions
What is specific heat capacity?
Energy needed to raise temperature of 1 gram of water by 1°C
Why does water have a high specific heat capacity?
Many hydrogen bonds absorb energy before breaking
What is the benefit of water’s high specific heat capacity to organisms?
It helps maintain stable body temperature
What is latent heat of vaporisation?
Energy needed to evaporate 1 gram of water
Why does water have a high latent heat of vaporisation?
Many hydrogen bonds need to be broken to evaporate water
How does water act as a cooling mechanism?
Evaporation of water takes heat energy away from the surface
How does ice act as an insulating layer?
It floats and prevents the water below from freezing
What type of reactions use water to break down complex molecules?
Hydrolysis reactions
What type of reactions release water to join molecules together?
Condensation reactions
What is cohesion?
Tendency of water molecules to stick together
What is adhesion?
Tendency of water to stick to other materials
How does cohesion and adhesion help water flow through organisms?
They help water move through xylem in plants
What does high surface tension in water allow?
It allows small organisms to be supported on the surface
