chemistry paper 2

  • Created by: 14ruddlee
  • Created on: 22-11-18 19:51

precipitiation and colour change

  • you put sodium thiosulfate into a clonical flask and put in hydrochloic acid also.
  • place this flask onto a white tile with a black cross in the centre of it 
  • swirl the solution slowly and time how long that it takes to make the cross disappear when a white precipitate form (when it goes cloudy)
  • stop the clock once the cross has diserpeared
  • change the concentration of the sodium thiosulfate each time you repeat the investigation and record your results
  • each concentration should take a different amount of time
  • the control variable would be the amount of sodium thiosulfate and the person who is carrying out the investigation because the investigation can be very subjective
  • the independant variable will be the concentration of the sodium thiosulfate
  • the dependant variable will be the time that it takes for the cross the no longer been able to be seen.

reversable reactions

  • reversable reactions will reach equilibrium
  • when the forward reaction is exactly the same as  the backwards reaction the reaction has reached equilibrium
  • if the equilibrium is on the right that means that the concentration of the the reactants is more than the reactants
  • if the equilibrium is on the left the concentration of the reactants is greater than that of the products
  • the position of the equilibrium depends on the following conditions:
  •                    temperature
  •                    pressure
  •                    concentration
  • if a reversable reaction is endothermic in one direction then it will be endo thermic in the other and visa versa








this helped me alot

this did not help me at all

maybe this helped me

maybe not

I don't know....