ENERGY CHANGES - ENERGY TRANSFERS
Doc Brown's Chemistry KS4 science GCSE/IGCSE/GCE-AS Revision Notes
Exothermic and Endothermic Energy Changes
Energetics Introduction - energy transfers in physical state changes and chemical reactions, simple calorimetry, calculations etc.
Energy changes are an important facet of chemical reactions. The interaction of molecules or ions often involves changes in energy due to the breaking and forming of bonds. Chemical reactions which release energy are called exothermic reactions, and those that take in (absorb) heat energy are endothermic. These energy transfer changes produce heating or cooling effects that can be used in a range of everyday applications.
Interactions between ions in an electrolyte can be used to produce electricity e.g. in cells and batteries. The reverse can be carried out and electricity can also be used to split ionic substances and is a useful means of producing elements that are too expensive to extract any other way. These topics are dealt with in the electrochemistry sections (see end of energy changes index too).
If you are an A Level student, these pages will help as an introduction, but then you should follow the A Level links to the more advanced revision notes and calculation methods - link below. These revision notes on energy transfers in chemical reactions should prove useful for the new AQA chemistry, Edexcel chemistry & OCR chemistry GCSE (9–1, 9-5 & 5-1) science courses.
Sub-index for ENERGY CHANGES (GCSE/IGCSE/O level)
The original page has now been split into 4 sections for GCSE/IGCSE/O Level science-chemistry students
1. Heat changes
2. Reversible Reactions and energy changes
Now on separate page PART A
3a. The significance of activation energy
3b. Further examples of reaction progress profiles
Now on separate page PART B
Now on separate page PART C
The basic principles of calorimetry
Now on separate page PART D
Revision notes on heat transfer energy changes in chemistry KS4 Science GCSE/IGCSE/O level Chemistry Information on heat transfer energy changes in chemistry for revising for AQA GCSE Science, Edexcel Science chemistry IGCSE Chemistry notes on heat transfer energy changes in chemistry OCR 21st Century Science, OCR Gateway Science notes on heat transfer energy changes in chemistry WJEC gcse science chemistry notes on heat transfer energy changes in chemistry CIE O Level chemistry CIE IGCSE chemistry notes on heat transfer energy changes in chemistry CCEA/CEA gcse science chemistry (revise courses equal to US grade 8, grade 9 grade 10) science chemistry courses revision guides explanation chemical equations for heat transfer energy changes in chemistry educational videos on heat transfer energy changes in chemistry guidebooks for revising heat transfer energy changes in chemistry textbooks on heat transfer energy changes in chemistry
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