• We need your support!

    We are currently struggling to cover the operational costs of Xtremepapers, as a result we might have to shut this website down. Please donate if we have helped you and help make a difference in other students' lives!
    Click here to Donate Now (View Announcement)

Help have exam tomorrow AS Biology- 31 doubts

Messages
324
Reaction score
24
Points
28
can any 1 explain me the steps i dont understand ....

practical doubt 1.jpg


This is form 2011 may june...
i dont understand the steps can some1 please quickly help me out
i need explaination on this.....
 
Messages
324
Reaction score
24
Points
28
please someone reply to this thread i am in deep need of guidance!!!!!!!!!!!!!!!
 
Messages
16
Reaction score
30
Points
3
basically you first make the serial dilutions ..then you perform the experiment without any copper sulfate... i.e place idoine drops as marked on tile and then add a drop of the solution in test tube at 15 seconds to the first one at 30 sec to second one..and son and record the time taken for colour to change and then repeat with various concentrations of copper sulfate..to see what effect it has on reaction rate :)
 
Messages
324
Reaction score
24
Points
28
basically you first make the serial dilutions ..then you perform the experiment without any copper sulfate... i.e place idoine drops as marked on tile and then add a drop of the solution in test tube at 15 seconds to the first one at 30 sec to second one..and son and record the time taken for colour to change and then repeat with various concentrations of copper sulfate..to see what effect it has on reaction rate :)

if i keep on adding 1cm cube of copper sulfate sol. to the next testube and add 9 cm of distilled water to it and so on..
then wudn't the 2nd and 3rd test tube wud have 9cm cube in volume since we are transferring 1 cm cube after adding distilled water.................
 
Messages
16
Reaction score
30
Points
3
what you do is take two cm3 of first solution and 18 cm3 of water..then separate it and keep one part for the experiment...use the other for the next dilution :)
 
Top