Iodine clock experiment

Question 1

What does this reaction determine?

Answer 1

= time how long it takes for colpur change to occur

Question 2

What do we add?

Answer 2

= sodium thiosulfate and starch, acts as an indicator
= reacts immediatley, to form iodine
= this is done by putting the flask onto a paper with a cross, and timing how long this dissapears
= when there is no sodium thiosulfate left, the iodine reacts with the starch, to produce a black colour
= change the concentrations of iodine, or hydrogen peroxide, and keep everything else constant, the time would change so we can calculate order

Question 3

What would be the method?

Answer 3

= make solutions of different concentratins of H2O2
= 1,0.8,0.6,0.4,
= measure out H+ and I- ions
= add to beaker conical flask
= add small amounts of inducator
= add 1 mold6M3 of h2o2 and measure time take for blue/baclk to form,
= repeat using sa,e volume and same concentration of H+ and I- ions
= rate 1/t