EX11 Oscillating Chemical Reaction
Oscillating chemical reaction
Aim:
The overall reaction rate and concentrations of some reaction intermediates of certain chemical reactions oscillate, even in a homogeneous system. This phenomenon is commonly found in living organisms. These periodical variations occur when a feedback mechanism is available in which a product changes the reaction rate. In this experiment will produce oscillations in both time and space in the concentrations of cerium(IV) and cerium(III) in the BZ reaction. Use the magnetic stirrer bar as experimental techniques and temporal oscillations visualized by Ferroin indicator. this experiment was use the Belousov-Zhabotinskii (BZ) oscillating chemical reaction mechanism briefly discuss the main features of this complex reaction.
Methodology:
Section A – Temporal oscillations visualised by Ferroin indicator
Rinse a 100 mL conical flask and a measuring cylinder with deionized water three times as the BV reaction is inhibited by traces of chloride ion. Place a magnetic stirrer bar into the conical flask and add 10 mL of 1.38 M malonic acid solution, 0.312 M potassium bromate solution, 7.5 M sulfuric acid and 3 × 10-3 M Ferroin. Place the flask on a magnetic stirrer plate and switch the stirrer plate on. Leave the stirrer plate on and do not change the stirrer speed for the duration of the experiment. Add the 6ml of 0.05 M (NH4)2Ce(NO3)6 solution and start the electronic timer.
Section B – Temporal oscillations recorded on a computer
Rinse a 100 mL beaker, a 50 mL beaker and a measuring cylinder with deionised water three times. Place a magnetic stirrer bar into the 100 mL beaker and add 10 mL of 1.38 M malonic acid solution, 0.312 M potassium bromate solution and 7.5 M sulfuric acid. Place the beaker on a magnetic stirrer plate and switch the stirrer plate on. Keep the constant speed of stirrer during this experiment. Into the 50 mL beaker add 30 mL of silver nitrate solution. Soak a piece of filter paper in potassium nitrate solution and
Aim:
The overall reaction rate and concentrations of some reaction intermediates of certain chemical reactions oscillate, even in a homogeneous system. This phenomenon is commonly found in living organisms. These periodical variations occur when a feedback mechanism is available in which a product changes the reaction rate. In this experiment will produce oscillations in both time and space in the concentrations of cerium(IV) and cerium(III) in the BZ reaction. Use the magnetic stirrer bar as experimental techniques and temporal oscillations visualized by Ferroin indicator. this experiment was use the Belousov-Zhabotinskii (BZ) oscillating chemical reaction mechanism briefly discuss the main features of this complex reaction.
Methodology:
Section A – Temporal oscillations visualised by Ferroin indicator
Rinse a 100 mL conical flask and a measuring cylinder with deionized water three times as the BV reaction is inhibited by traces of chloride ion. Place a magnetic stirrer bar into the conical flask and add 10 mL of 1.38 M malonic acid solution, 0.312 M potassium bromate solution, 7.5 M sulfuric acid and 3 × 10-3 M Ferroin. Place the flask on a magnetic stirrer plate and switch the stirrer plate on. Leave the stirrer plate on and do not change the stirrer speed for the duration of the experiment. Add the 6ml of 0.05 M (NH4)2Ce(NO3)6 solution and start the electronic timer.
Section B – Temporal oscillations recorded on a computer
Rinse a 100 mL beaker, a 50 mL beaker and a measuring cylinder with deionised water three times. Place a magnetic stirrer bar into the 100 mL beaker and add 10 mL of 1.38 M malonic acid solution, 0.312 M potassium bromate solution and 7.5 M sulfuric acid. Place the beaker on a magnetic stirrer plate and switch the stirrer plate on. Keep the constant speed of stirrer during this experiment. Into the 50 mL beaker add 30 mL of silver nitrate solution. Soak a piece of filter paper in potassium nitrate solution and