2H 2​ O 2​  (l)→ 2H 2​ O (l)+ O 2​ This reaction can be catalyzed by an enzyme (catalase) or by a non-biological catalyst (Manganese IV oxide)Method:Put 3 cm3 of hydrogen peroxide in a test tube.Add fresh potato strips and shake gently.Keep your thumb on top of the test tube, or use a stopper, to retain the gas.Do the “glowing splint” test → the splint relightsPositive control: repeat original experiment using manganese IV oxide → bubbles of O2 formConclusion: Reaction happens because of a catalyst1st negative control: repeat original experiment using boiled potato strips → nothing happensConclusion: Enzymes denature when they are at high temperatures2nd negative control: repeat original experiment using water instead of hydrogen peroxide → nothing happensConclusion: hydrogen peroxide is the substrate3rd negative control: repeat in a cold environment, the effervescence should be slowerConclusion: enzymes don’t work as well in the cold

Why does potato and onion bubble up when you put in a hydrogen peroxide solution?

*19* Turn over ► IB/M/Jun23/8464/C/2H Do not write outside the box 0 6 . 1 The equation for the decomposition of hydrogen peroxide is: 2 H2O2 → 2 H2O + O2 Describe a test to identify the gas produced in the reaction. [2 marks] Test Result

Oxygen and water are produced when hydrogen peroxide breaks down. The chemical term for this process is decomposition. The decomposition of H2O2 happens naturally at a slow rate, as shown in the equation below:2H2O2 (aq) → 2H2O (l) + O2 (g)Outline how you would test that oxygen was produced.

Which of the following reactions will produce hydrogen? Acid plus alkaliMetal plus oxygenMetal plus acidMetal carbonate plus acid2What is the test for hydrogen gas?Turns limewater cloudy whiteBleaches damp blue litmus paperRelights a glowing splintA lit splint produces a squeaky pop3The test for oxygen is based on the fact that fuels need oxygen to burn. What fuel is used in this test? Litmus paperMethaneLimewaterA glowing splint4Which of the following reactions will produce carbon dioxide? Metal carbonate plus acidMetal plus acidAcid plus alkaliMetal plus oxygen5What happens when carbon dioxide is bubbled into limewater? It turns from colourless to cloudy whiteIt turns from cloudy white to colourlessIt turns from colourless to blueIt produces a flame6What is the test for chlorine gas?Turns damp red litmus paper blueTurns limewater redBleaches damp blue litmus paperBurns with a lilac flame

You decomposed hydrogen peroxide in the lab. You and your partner do not agree on what the chemical reaction is. The following are the proposed reactions: Your reaction:H2 O2 → H2 + O2 Your partner’s reaction: 2 H2 O2 → 2 H2 O + O2 The following data was collected: Mass of Beaker36.39 g Mass of Beaker and H2 O2 before Rxn 41.31 g Mass of O2 gas Collected during Rxn 2.32 g Using the data above, prove which reaction is correct. Support your answer with stoichiometry.