Science behind a hot air balloon Investigation into gas laws

James Lovatt School of Education Studies Centre for the Advancement of Science and Mathematics Teaching and Learning Dublin City University, Ireland Version 1.1

Overview

•

These slides will give an outline of one way to use IBSE to teach the gas laws

•

The slides will detail the main areas and the notes section will provide more detail and links to resources

•

Please view and print out notes section for detailed information and resource links

Introductory section and preparatory phase • Short Description: Students will investigate the gas laws in the context of an interdisciplinary team developing a hot air balloon using an IBSE approach • Keywords: Gas laws, experimental design, data logging, graphing, data analysis and interpretation, presentations, physics, chemistry • Age range: 13-18 • Context: School or university with modifications • Time required: 2 x 40 mins and 1 x 80 minute classes * *see note section

Key Features

• • • • • • • Video to attract attention and give context Group discussion and question development on context Use of simulations and computational models to develop understanding Student experimental design and technology based instrumentation Data analysis and interpretation Feedback and reflections Assessment to develop skills and learning

Introductory section and preparatory phase • Technical requirements: computer, projector, internet connection, data loggers and sensors (pressure, temperature), general laboratory equipment • Author’s background: Teacher educator / former teacher • Connection with curriculum: air and oxygen, measurement, pressure, density and floatation, heat and heat transfer – (topic titles from Irish curriculum)* • 2.

3.

4.

5.

6.

7.

8.

Learning objectives: Students will: 1.

learn about scientific methods by designing and carrying out their own experiment to determine relationship between temp/volume/pressure of gases develop observational and psychomotor laboratory skills develop questioning skills and experience of inquiry process graph experimental results and analyse findings to determine gas laws develop communication skills through peer cooperative learning, and final assessment develop ICT skills through use, data loggers of excel graphing and video presentation develop research skills when inquiring about task requirements develop observational and psychomotor laboratory skills

Introductory section and preparatory phase • Guidance for preparation: (re-read after reading entire document) – – – – – Teacher should complete all of the experiments in advance to make sure all equipment needed is available and to identify any hazards or difficulties their students may have* Teacher should plan questions to direct learning in the context of their students abilities* In advance of class, necessary equipment should be made ready for students but additional equipment could be provided for students who want to try different procedure* Teacher must decide how far students can go with their experimental design and build in stages where students may need to be brought back on track* Depending on ability of students and experience with inquiry some guided worksheets could be developed to aid students through the tasks

Teaching Phase 1 • Use a video of a hot air balloon to grab students attention ( http://www.youtube.com/watch?v=EzC20qqASnI&NR=1 ) and give them an appropriate task* • Follow up video with students questions as per task in notes • Follow this discussion about the construction of a hot air balloon* (very brief) • Divide students into groups – Task (make list of all aspects that would need to be considered if making a hot air balloon)

Teaching Phase 2 • Students present findings from group work from (TP1) • Discuss, clarify and correct some of students answers if necessary still leaving scope for further inquiry • Focus discussion on gas laws to direct students thinking then introduce task*

Teaching Phase 2 • Outline Task: You are part of a team to develop a hot air balloon. You are responsible for investigating the science behind getting a hot air balloon airborne - you have three subtasks:* 1.

Investigate how hot air balloons operate 2.

Investigate the relationship between temperature, volume and pressure of gases 3.

Devise and carry out experiments to determine the relationships between temperature, volume and pressure of gases using air as the gas (graph and tabulate all findings) 4.

Make a written report and presentation (this can be video or oral) of your experimental findings and advise the team on what will be required to get the air balloon airborne

Teaching Phase 2/3 Facilitation / Feedback / Discussion Junctures Include several facilitation junctures These will allow for direction and development of student thinking and questioning skills 1.

2.

3.

4.

Feedback on findings on how a balloon works Feedback on planned experimental design Facilitation during experiment / modifications to experiment design etc.

Feedback on experiment conclusions

Teaching Phase 4/5 - Assessment • Students should present their work to class • Class discussion should be held on the following – – Findings presented Student ‘process challenges’ (researching, experimental design, concept understanding, data analysis, skills, group work) • Teacher should give an overall summary/clarification and reflection on findings and process issues linked to students contribution

Follow up activities • Depending on the age group / level of the class the teacher could use TP5 Reflection to identify further areas for discussion that students could then investigate areas such as: – – – – – – – How would weather conditions effect flight?

Different gas properties (helium balloons) What temperature does the gas have to reach?

Size of balloons are there any limitation factors?

How are balloons directed – physics of flight Students could use their findings to make a balloon in class Materials science for hot air balloons