Properties of Transverse & Longitudinal Waves In mechanical waves, particles oscillate about fixed points The direction of oscillations with regards to the direction of wave travel determine wh...
Edexcel IGCSE Chemistry 复习笔记 4.3.2 Halogens & Alkanes Halogens & Alkanes In a substitution reaction, one atom is swapped with another atom Alkanes undergo a substitution reaction...
Edexcel IGCSE Chemistry 复习笔记 4.3.1 Alkanes The Alkanes Alkanes are a group of saturated hydrocarbons The term saturated means that they only have single carbon-carbon bonds, there are no...
Edexcel IGCSE Chemistry 复习笔记 4.2.4 Cracking Cracking Saturated molecules contain single bonds only whereas unsaturated molecules contain double bonds between their carbon atoms Alkanes a...
Edexcel IGCSE Chemistry 复习笔记 4.2.3 Nitrogen Oxides & Sulfur Dioxide Formation of Nitrogen Oxides Nitrogen Oxides These compounds (NO and NO2) are formed when nitrogen and oxygen reac...
Edexcel IGCSE Chemistry 复习笔记 4.2.2 Combustion Fuels & Combustion The combustion of fossil fuels is the major source of atmospheric pollution Fossil fuels include: coal, oil, natural ...
Edexcel IGCSE Chemistry 复习笔记 4.2.1 Crude Oil & Fractional Distillation Crude Oil & Fractional Distillation Crude oil as a mixture is not a very useful substance but the different...
Wave Intensity Progressive waves transfer energy The amount of energy passing through a unit area per unit time is the intensity of the wave Therefore, the intensity is defined as power per unit ar...
Edexcel IGCSE Chemistry 复习笔记 4.1.3 Classifying Organic Reactions Classifying Organic Reactions The reactions of organic compounds can be classified into substitution, addition and combus...
