Water

• Why is water considered a polar molecule?

  Because it has a difference in charge across the molecule.
• What type of bonds form between water molecules?

  Hydrogen bonds.
• Why is water important for chemical reactions?

  Water is an important metabolite in many metabolic reactions.
• Why is water a good solvent?

  Because its polar nature allows it to dissolve ionic compounds and polar molecules.
• What types of molecules can dissolve in water?

  Ionic compounds and polar molecules like glucose.
• What is latent heat of vaporisation?

  The amount of heat energy needed to turn a substance into a gas.
• Why does water have a high latent heat of vaporisation?

  Because a lot of energy is required to break the hydrogen bonds between water molecules.
• How does water's high latent heat of vaporisation help organisms?

  It allows small amounts of water to have a large cooling effect with little loss through evaporation (e.g. sweating).
• What is specific heat capacity?

  The amount of energy needed to raise the temperature of 1g of a substance by 1°C.
• Why does water have a high specific heat capacity?

  Because hydrogen bonds absorb a lot of energy before they break.
• How does water's high heat capacity benefit organisms?

  It helps prevent rapid temperature changes, maintaining stable temperatures in aquatic environments and inside organisms.
• Why does water have stable temperatures compared to land?

  Because water absorbs a lot of heat energy before its temperature increases.
• What is cohesion?


  The attraction between molecules of the same substance.
• Why do water molecules stick together?

  Because they are polar and form hydrogen bonds.
• How does cohesion help plants?

  It supports columns of water in the transport cells of plants.
• What is surface tension?

  The force that allows a liquid to resist an external force.
• How does surface tension allow insects to walk on water?


  It allows insects to walk on water by providing a supportive surface.