I did an experiment to determine the rate of the reaction. We did 4 different tr

Question

I did an experiment to determine the rate of the reaction. We did 4 different trials using buffered iodide solution (25.0 mL of acetic acid/sodium acetate buffer; 6.0 mL of 0.5 starch solution, 6.0 mL of 0.3 M KI; and distilled water), 0.025 M thiosulfate solution (5.0 mL of 1.0 M Na2S2O3 and distilled water) and peroxide solution (30 mL of 1.0 M H2O2 and distilled water). First trial: 40.0 mL of buffered iodide solution, 10 mL of thiosulfate solution and 10 ml of distilled water reacting with 20 mL of peroxide solution. How do I calculate the moles of sodium thiosulfate on each trial and the mol/l of H202 reacted

Explanation / Answer

(i) The moles of sodium thiosulphate = molarity X volume

Molarity of thiosulphate = 0.025

Volume of thiosulphate = 10mL = 10/1000 L = 0.01L

Moles of thiosulphate = 0.02 X 0.01 moloes = 0.0002 moles

(ii) Moles / L of H2O2

Moles of H2O2 = Molarity x volume

Molarity of diluted H2O2 = Molarity X volume / 150mL = 1 X 30 / 150

(150mLis used for diluting H2O2)

Molarity of H2O2 = 0.6M

Moles of H2O2 = Molarity X volume = 0.6 X 20 /1000 = 0.012 moles

Total volume = 10mL thiosulphate + 10 mL distilled water + 20mL H2O2 = 40mL = 40/1000 L

Moles of H2O2 / L = 0.012 X 1000 / 40 = 0.3 M

Related Questions

Navigate

• Browse (All)
• Browse I
• Subjects

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