34 What sank the Kursk? 14-16 Working in groupsSelf assessmentPeer assessmentSharing objectives and criteriaQuestioningUsing feedbackUsing tests

In this activity, students plan an investigation into the effect of catalysts on the rate of a reaction. The activity is placed in the context of finding out what sank the Russian nuclear submarine Kursk, and begins with stimulus material in the form of a text document and a teacher demonstration.

After checking and evaluating their experimental plan students carry out practical work, share results and agree on conclusions. Finally, they work in groups to extract information from unfamiliar but contemporary texts.

Learning objectives

Students will be able to:

  • understand that the rate of some reactions can be increased using a catalyst
  • devise an experimental investigation.

Sequence of activities

Several days before the first session, give each student a copy of the News timeline to read, so that they have an answer to the question ‘What sank the Kursk nuclear submarine?’

At the start of the session, ask what they have found from reading the News timeline.

Many points arise here but they should include that the sinking of the Kursk involved hydrogen peroxide.

Project or display the Seismic data table.

Arrange students in pairs and issue a mini whiteboard to each. Ask the pairs to write down what information they can deduce from the table.

There were two explosions at roughly the same place in quick succession, the second more powerful than the first.

Demonstrate the decomposition of hydrogen peroxide in a narrow-necked conical or flat-bottomed Pyrex glass boiling tube.

Pose questions to highlight that the decomposition:

  • has been accelerated by the presence of a catalyst
  • occurs at a sufficiently high temperature to vaporise the water
  • proceeds at a very fast rate, rather like an explosion.

Now share the learning objectives with the students.

Explain that they are to plan an experiment to compare how effective different powders are in catalysing the decomposition of hydrogen peroxide.

  • Take the students through the equipment and materials that are available.
  • Give each student a What sank the Kursk? Worksheet and an Apparatus list.
  • Ask them to draw a diagram of their apparatus for when they begin their experiment.
  • After a suitable time, give out copies of the Apparatus diagram, showing the expected apparatus.
  • Pose questions to make explicit why that apparatus has been chosen.
  • Ask the students to compare their diagram with the one they have been given.
  • Get them to write down an experimental procedure based on the Apparatus diagram they have been given (and which someone else could follow).
  • After a suitable time give out copies of the Procedure sheet detailing the expected procedure.
  • Pose questions to highlight why the procedure has been chosen.
  • Ask students to compare their experimental procedure with that on the Procedure sheet.

Supervise the students as they carry out the practical, organising them to:

  • work in pairs
  • follow the Procedure sheet using one of the powders (allocate different powders to different pairs)
  • record their results in the table provided.

Arrange for the pairs to:

  • share their results so that they can complete their table
  • combine with other pairs to agree what conclusions they can draw from the shared results.

Bring together students in a plenary.

Select individual students to give their conclusions.

Encourage other students to add to these.

Pose questions to ensure that all students have understood that the decomposition of hydrogen peroxide can be catalysed by some, but not all, solids.

Give a copy of Peroxide power in torpedoes to each student. They are to read the three reports and to answer the questions that follow.

Circulate and support the students while they:

  • work in groups
  • share their answers
  • agree a group answer
  • write down what they have learned about extracting information from an unfamiliar piece of text.

Bring together students in another plenary. Ask:

  • individual students to give answers to some of the questions
  • other students to add to these answers
  • about the connection between the teacher demonstration, the student experiments and what happened on the Kursk.

Assessment for learning commentary

The introductory work on the sinking of the Kursk and the teacher demonstration of the decomposition of hydrogen peroxide provides a relevant opportunity for the teacher to share the learning objectives with students.

Students appraise their own experiment plan by comparison with exemplars and this enables them to recognise the standards they are aiming for. When they compare their experimental results with those of others they build their ideas about how some solids can catalyse the decomposition of hydrogen peroxide.

As a further refinement, students extract information from an unfamiliar text and they review their own skills in this area.

Resources

Props

For each student

Download Word Download PDF News timeline
Download Word Download PDF What sank the Kursk? worksheet
Download Word Download PDF Apparatus list for finding out which powders catalyse the decomposition of hydrogen peroxide
Download Word Download PDF Apparatus diagram
Download Word Download PDF Procedure for finding out which powders catalyse the decomposition of hydrogen peroxide
Download Word Download PDF Peroxide power in torpedoes
  • Mini whiteboard

For the demonstration

Download Word Download PDF Projected image of picture of the Kursk submarine

Equipment

For the demonstration of the catalytic decomposition of hydrogen peroxide

  • 500 cm3 narrow­‑necked conical or flat‑bottomed pyrex glass boiling flask with a tight fitting stopper
  • Aluminium foil
  • About 20 cm invisible nylon thread
  • Empty tea bag cut along one edge
  • Enough manganese(IV) oxide (Harmful) to fill the tea bag
  • 40 cm3 of 100 volume hydrogen peroxide (Corrosive)
  • Eye protection (goggles).

For each pair of students to investigate the effect of different powders on the decomposition of hydrogen peroxide

  • Trough
  • 50 cm3 burette which will be inverted
  • 250 cm3 conical flask with bung fitted
  • About 75 cm3 of 20 volume hydrogen peroxide per test (Irritant)
  • Range of powders to test: zinc oxide, iron(III) oxide, copper(II) oxide (Harmful), manganese(IV) oxide (Harmful), powdered zinc, powdered iron, powdered copper (one powder per pair)
  • Small test-tube
  • Rubber tubing to connect side arm of flask to bottom of upturned burette
  • Boss, clamp and stand
  • Stop clock
  • Cotton thread
  • Funnel
  • 100 cm3 measuring cylinder
  • Balance weighing to 0.01 g
  • Eye protection.

Data Table

Signals recorded by a seismic station in Northern Norway on 12 August 2000.

Latitude /°N Longitude /°E Report time GMT Richter scale magnitude
69.70 37.58 07.28.27 1.5
69.57 37.64 07.30.42 3.5

Safety notes

It is the responsibility of the teacher to carry out appropriate risk assessments.

For the teacher demonstration

  • Wear eye protection.
  • Use a safety screen.

Principal hazards for the student practical

  • Hydrogen peroxide
  • Depends on powders selected.

Answers

Peroxide power in torpedoes

  1. Why did HMS Sidon sink? 
    A torpedo exploded accidentally because a stainless steel pipe carrying HTP burst, spraying the inside of the torpedo with superheated water, pure oxygen and hydrogen peroxide under pressure, causing an uncontrolled reaction.
  2. Why did the Royal Navy stop using HTP-powered torpedoes?  
    They were considered too dangerous after the Sidon incident.
  3. What type of torpedo was Kursk carrying according to The Red Star? 
    The Red Star stated that the Kursk was carrying torpedoes involving potentially dangerous liquid fuel.
  4. Why was the Kursk carrying this type of torpedo?
    The Kursk had been refitted in a ‘modernisation’ programme designed to save money.
  5. Why was the story removed from The Red Star's website?
    The story was probably removed because it was too near the truth and at that time the Russian navy didn’t want to admit this.
  6. What does the torpedo designer think about the Kursk and Sidon accidents?
    The torpedo designer thinks that the Kursk and Sidon accidents were caused by the same thing ‑ leakage of HTP followed by an explosion due to build up of gas.

Acknowledgement

V. Kind, Contemporary chemistry for schools and colleges. London: Royal Society of Chemistry, 2004.