What observations and conclusions can you note about each of the three reactions

Question

What observations and conclusions can you note about each of the three reactions that occurred in the test tubes where you combined potassium iodide, KI, and hydrogen peroxide, H2O2 (in part 1) of the experiment?  (Give a detailed explanation of any observations that you made, i.e., what made the colour change, what reactions happened?)

To approximately 5 mL of KI solution in a test tube, add a 5 drops of peroxide solution. Record your observations and conclusions. Distribute the mixture among three test tubes. Retain one as a standard. To the second, add 2 drops of starch solution. To the third, add 2 millilitres of thiosulfate solution. What do you observe and what do you conclude? Add 2 drops of starch solution to the third tube. Does your conclusion require amendment?

Have anyone done this kind of experiment before?

Explanation / Answer

Hi, This is an experimental question and you are suppose what you observe in lab while doing the experiment.

Theoretically , Below changes should happen

reaction 1:
2 KI(aq) + H2O2(aq) <---> 2 KOH(aq) + I2(aq)
When KI and H2O2 are mixed, solution had diddoved I2 which is voilet in color.

reaction 2:
When starch is added, solution turns blue-black in color.

reaction 3:
when sodium thiosulfate, Na2S2O3 is added to it, potassium triiodide, KI3 is formed. So solution will turn red. Here Iodine is reduced and Na2S2O3 is oxidised. It is oxidation-reduction reaction.

Related Questions

Navigate

• Browse (All)
• Browse W
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.