Water Flashcards
what are the cohesive properties of water
molecules of the same type (water) are attracted to each other
what is hydrogen bonding
electrostatic force of attraction between a hydrogen atom covalently bound to a more electronegative atom or group
gives water its unique properties
what are the adhesive properties of water
any attraction between two unlike molecules
- capillary action: transport of water up vascular column via transpiration stream involves both cohesion (water - water) and adhesion (water - cellulose)
what are the thermal properties of water
high specific heat capacity: amount of energy required to raise the temperature of water is high due to hydrogen bonds
high latent heat of vaporisation: heat energy required to evaporate water is relatively high (cooling effect)
high boiling point
what are the solvent properties of water
polar nature of water: forms shells around other polar molecules which dissolves them and keeps them in solution (cytoplasm)
what are some examples of water as a solvent in plants and animals
water medium of transport in vascular tissue:
- xylem carries water and dissolved sugars from leaves to stem/roots/flowers of a plant
blood as a medium of transport in animals:
- blood plasma: liquid portion of blood/carries solutes such as glucose/amino acids/fibrinogen/hydrogen carbonate ions
what happens to covalent and ionic molecules in water
ionic molecules: dissociate (separate into ions)
polar covalent: dissolve (molecules stay together and bond with water)
non polar covalent: does not dissolve (repels and forms layers)
what are hydrophilic and hydrophobic substances
hydrophilic: chemically attracted to water
hydrophobic: non polar and not attracted to water
what makes water have a polar covalent bond
unequal sharing of electrons between O and 2H
H atoms slightly positive and O atom slightly negative
what is the significance of water
required for anabolic construction of organic molecules via condensation
essential to acid-base neutrality and enzyme function
