1100602EN_PR_Blue_Bottle_Experiment

BLUE BOTTLE EXPERIMENT

CHEMISTRY DEMONSTRATION EXPERIMENT IN ORGANIC CHEMISTRY

DEMONSTRATION EXPERIMENT IN SECONDARY STAGE II

BLUE BOTTLE EXPERIMENT

524 013

Sensor-CASSY 2

EXPERIMENT C2.2.2.2

524 220

CASSY Lab 2

The blue bottle experiment is a favourite demonstration experiment in practical lectures. In the classic version, the experimenter shakes a bottle filled with a clear liquid which then turns blue. After a while the liquid becomes colourless, but then turns blue again through shaking.

The experiment is based on the redox indicator, methylene blue. Methylene blue is blue in its oxidised form, and in its reduced form, the so-called leucomethylene blue, it's colourless.

CONTENTS OF THE BLUE BOTTLE EXPERIMENT 524 013

Sensor-CASSY 2

524 220

CASSY Lab 2

524 069

Immersion photometer S

666 425

Profile frame C50, two rows, for CPS

666 438

Woulff‘s bottle with manometer, CPS

667 3095

Screw cap, GL 45, mB

667 3107

Silicone gasket, GL 45/26, set of 10

666 482

Aeration pump, controllable, CPS

501 44

Connecting leads 19 A, 25 cm, red/blue, pair

667 7977

Compact balance 440-3N, 200 g: 0.01 g

664 157

Watch glass dish, 125 mm diam.

666 966

Spoon-ended spatula, SS, 180 mm

666 003

Pipetting ball (Peleus ball)

665 996

Graduated pipette 5 ml

665 756

Measuring cylinder 500 ml with plastic base

604 501

PVC tubing 7 mm diam., 1 m

604 460

Hose clamp 8...12 mm

602 347

Laboratory bottle to DIN standard, 500 ml , GL 45

673 2920

Löffler's methylene blue solution, 100 ml

673 6800

Sodium hydroxide pellets, 100 g

672 1100

D(+)-Glucose, 100 g

675 3400

Water, pure, 1 L additionally required: PC with Windows XP/Vista/7/8 Blue bottle experiment

Our version is a modification of the classic blue bottle experiment. Instead of shaking, the air is pumped through the reaction mixture. This takes place automatically. The transmission of the solution is continually measured using an immersion photometer. As soon as the solution has become colourless, air is pumped through until the solution is coloured deep blue again. The pump then switches off automatically. The solution slowly loses its colour and the process then begins anew.

TOPICS The use of carbohydrates such as glucose as reducing agents Performing the blue bottle experiment in a new, automated version

Setting up and using a two-point control system Photometry using an immersion photometer Learning about organic redox reactions and the redox indicator methylene blue

WWW.LEYBOLD-SHOP.COM BRANDS OF THE LD DIDACTIC GROUP

1100602EN

C2.2.2.2

Here, the reducing sugar glucose acts as the reducing agent. It reduces methylene blue to colourless leucomethylene blue. By shaking, oxygen diffuses through the solution and re-oxidises the leucomethylene blue to methylene blue. This is then reduced again by the glucose. The reaction continues to run until there is no more oxygen available in the air or the glucose reducing agent has been depleted.