Difficult ideas in Chemistry
Particles which do not change amidst change, burning which builds up oxides, the funny pH scale, reaction rates - how do we approach these difficult ideas? - We explore some of the barriers to understanding our chemical environment, starting with those particles which do not change even though things burn, grow, rot and evaporate around us.
- Then we examine the process of burning which is a constructive process with energy stored in the fuel/oxygen system (no energy is stored in food or fuels!).
- The gaseous oxides of combustion are acidic and the solid ashes are alkaline, but what is this strange pH scale?
- And why do slow reactions get so much faster as the temperature rises – a 10 degree rise in temperature often doubles the rate? (Think of the time it takes milk to go sour – 8 days in the ‘fridge at 4 degrees, 4 days in a cool house at 14 degrees, 2 days in a warm house at 24 and a day at 34 degrees.)
My talk will be exemplified by reactions we see in everyday life, and I will suggest ideas for helping students understand the underlying chemistry.
Attached is a draft of the PowerPoint I will use - the final version will be available after the conference.
About Keith Ross I started teaching science in school on VSO in India after a metallurgy degree at Oxford. After a year in industry I made teaching my career, first in secondary schools in Birmingham and Leicestershire, then for 3 years in Nigeria. I was deeply inspired by Clive Sutton during a Master's in Education at Leicester University and was involved with some of the early challenges made to the science national curriculum by Ros Driver and colleagues.
In1980 I moved to teacher education at what became the University of Gloucestershire at Cheltenham. I began by working with students from Africa on A level chemistry teaching. Later I became the science tutor for the GITEP post graduate secondary teacher education project and the book
“Teaching Secondary Science” now in its 4th edition was the outcome. Today’s talk is based on chapter 14 - 'Difficult ideas in Chemistry'.
In 2007-8 I worked with primary teachers in
a college of education in Pakistan, and more recently, retired and living in the South West of France, I have been helping to develop
chemistry videos for Fuseschool.
