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ExposeExciteIgniteMay2012

Introduction About this

Introduction About this book This book is simply a collection of my favourite exothermic combustion demonstrations that I have conducted in my classroom, during science shows and at science conferences. All of the activities have great intrinsic educational value and I have used them as such in my classroom. Notwithstanding - they are all very popular with students. I have liberally added subject content to the demonstrations so readers can have the knowledge and background information to turn a great demonstration into an educational event. The main intention of the book is to show you how the demonstrations are done. I tried to be as specific as possible when describing procedures so science teachers with basic chemistry skills can reproduce the activities. When I selected activities, I simply focused on three parameters: All activities had to be Simple, Spectacular & Safe. ! Simple: I know that teachers are busy and do not have the time to mix or put together elaborate concoctions. The same goes for home experimenters who want quick results. My experience is that success here will breed more success. Once you start venturing into the ‘extraordinary’, the feedback and success will propel you to the next level. ! Spectacular: Libraries and the internet provide an ample supply of books and webpages offering standard “mid-range” science content. This book offers those special spectacular activities that you require on open days and for special curriculum events. These are the ones your students are likely to remember long after they have forgotten your name . . . ! Safe: It had to be safe within the scope of being spectacular. Now that is a balancing act as this book is mostly about combustion! I have selected activities that do not use strong oxidants and have stuck to small volumes to keep it safe. You won’t find any chlorates or perchlorates in here. Also no peroxides or concentrated acids. But you will find heaps of energy produced by icing sugar, hydrogen gas and pencil sharpeners! 9

I have performed and conducted the described activities so many times that I may be able to perform them blind folded. They have been tested well and I gladly back them up with the confidence that they do work as described. This book also offers some of the practical “trade secrets” of chemistry teaching that no formal education ever passes onto new teachers. You won’t find the information mentioned here in education faculties, but the truth is that chemistry teachers in the trenches engage in spectacular Whizz-Bang stuff - without the training! It is important that teachers learn how to perform the spectacular demonstrations in a simple, safe and responsible way. Conducting demonstrations with potentially hazardous chemicals in front of an audience can be very challenging. Solid knowledge and guidance from those who have been there can fuel your confidence. Why do we do science demonstrations? Firstly, it is sometimes the only way in which we can link an abstract concept to the students’ world - the demonstration simply acts as a bridge between the real and abstract world. Talking about ”increased surface area as a factor that increases reaction rate” is abstract - but demonstrating the spectacular visual effect provides an experience to remember. Secondly, demonstrations provide powerful motivation and make the teaching and learning of chemistry much more enjoyable. After presenting (safely) to almost half a million students, I can testify to this. I wish you many hours of discovery and excitement with your students or in your own backyard. Let’s share the joys of chemistry, safely, with everyone! Carl Ahlers Australia, 2011 carl@profbunsen.com.au www.profbunsen.com.au Everything should be made as simple as possible, but not simpler. - Albert Einstein 10