The Structure and Function of Enzymes MODULE 1 MODULE 2 ...

What do Enzymes Do and How Do They Do It?Module 2 Engagement ActivitySilent Demonstration of CatalysisMaterials required: two test tubes, test tube rack, wooden splints, matches, manganesedioxide, 3% hydrogen peroxide, weighing scale, and filtering apparatus (funnel, funnelstand, filter paper, and waste beaker).Teacher ActivityStudent activityThe teacher announces that a silent demonstration isabout to take place. Students may neither ask questionsof the teacher nor talk to one another once thedemonstration begins. Students should move to wherethey can see the demonstration and record theirobservations as the demonstration takes place.The teacher simulates the weighing of a piece of filterpaper. A very small amount of manganese dioxide(MnO 2 ) is then placed on the filter paper and weighed.The masses are written on the chalkboard. Themolecular formula for MnO 2 is written on the board.The MnO 2 is placed in a test tube.The teacher pours hydrogen peroxide (H 2 O 2 ) into asecond test tube, filling the tube about a third of theway. The teacher points to the tube and writes themolecular formula for hydrogen peroxide on thechalkboard.The teacher performs the glowing splint test on eachtube (the test is negative – it does not burst into flames).The hydrogen peroxide is added to the MnO 2 (furiousbubbling is observed).The glowing splint test is performed on the tube. Thesplint ignites (this a positive test for the presence ofoxygen gas).The teacher pours the solution into the filteringapparatus. The filter paper is weighed. This is simulatedin such a way that the mass of MnO 2 remains the same.The mass is written on the chalkboard.End of silent demonstrationClosure Option 1. This presumes that the students havebeen exposed to fundamental chemistry.Closure Option 2. Students can analyze thedemonstration and come to conclusions with minimalteacher direction.Closure Option 3. The teacher directs a class discussionto guide students in making inferences.Move to where you can see;get materials out so that arecord of the demonstrationcan be made. Students logon to Blackboard.com andenter the discussion thread.Students record masses.Students record themolecular formula formanganese dioxide.Students record themolecular formula forhydrogen peroxide.Students record theapproximate amount ofliquid in the test tube.Observations are recordedObservations are recordedObservations are recordedObservations are recordedWrite the equation for thereaction that you observed.Write an abstract orsummary of thedemonstration.Verbal summation18