water Flashcards
what makes water a polar molecule?
- forms hydrogen bonds
- charge is unevenly distributed
- partially pos/neg regions
how many hydrogen bonds can water make?
4
why can water not dissolve non polar substances?
they have no regions of charge so cannot be attracted to water’s charges
how is a diagram of two water molecules drawn?
- displayed formula of H2O
- delta neg on oxygen
- delta pos on hydrogen
- dotted line between H and O on diff molecules
- line labelled ‘hydrogen bond’
what is a ‘hydrolysis’ reaction?
- bond is broken
- by adding water
what is a ‘condensation’ reaction?
- bond is formed
- by removing water
state 6 characteristics of water
- high bp
- ice less dense
- cohesive
- high latent evaporation heat
- high specific heat capacity
- incompressible
how does high boiling point relate to a function?
function = temp control
- strong hydrogen bonds require a lot of energy to overcome
- therefore water buffers extreme temperature changes
- provides a constant living environment
how does ice is less dense relate to a function?
function = habitat
- hydrogen bonds cause molecules to spread out when frozen
- floats on surface and provides an insulation layer for organisms living in a pond
how does cohesion relate to a function?
function = transport medium
- forms hydrogen bonds with other water molecules
- can move against gravity
- allows plants to uptake water from roots e.g. through xylem
- capillary action
how does high latent evaporation heat relate to a function?
function = temp control
- lots of energy required to change state
- provides a cooling effect
- constant environemnt
how does high specific heat capacity relate to a function?
function = habitat
- water absorbs heat before its temperature changes
- maintains homeostasis
- enzyme controlled reactions are successful
