Edexcel A Level Chemistry:复习笔记2.3.1 Group 7 Trends
Physical Properties The Group 7 elements are called halogens The halogens have uses in water purification and as bleaching agents (chlorine), as flame-retardants and fire extinguishers (brom...
Edexcel A Level Chemistry:复习笔记2.2.5 Flame Tests
Flame Tests Metal ions produce a colour if heated strongly in a flame Ions from different metals produce different colours The flame test is thus used to identify metal ions by the colour of...
Edexcel A Level Chemistry:复习笔记2.2.4 Group 2 Carbonates & Nitrates
Group 2 Carbonates & Nitrates Thermal decomposition is the breakdown of a compound into two or more different substances using heat Thermal decomposition of carbonates The Group 2 carbon...
Edexcel A Level Chemistry:复习笔记2.2.3 Group 2 Hydroxides & Sulfates
Group 2 Hydroxides & Sulfates Group 2 hydroxides Going down the group, the solutions formed from the reaction of Group 2 oxides with water become more alkaline When the oxides are dissol...
2022-23CTB全球创新研究大挑战火热组队中，全新课题等你来解锁！
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Edexcel A Level Chemistry:复习笔记2.2.2 Reactions of Group 2
Group 2 Elements Reactions with water and oxygen The reaction of group 2 metals with oxygen follows the following general equation: 2M (s) + O2 (g) → 2MO (s) Where M is any metal in group 2 ...
Edexcel A Level Chemistry:复习笔记2.2.1 Explaining Group 2 Trends
Ionisation Energy Chemical trends All elements in Group 2 (also called alkali earth metals) have two electrons in their outermost principal quantum shell All Group 2 metals can form ionic co...
Edexcel A Level Chemistry:复习笔记2.1.4 Ionic Equations
Writing Chemical Formulae Oxidation numbers are a useful tool for naming compounds as some elements can exist with more than one oxidation number For compound with two elements it is straigh...
Edexcel A Level Chemistry:复习笔记2.1.3 Redox & Disproportionation
Disproportionation Disproportionation reactions A disproportionation reaction is a reaction in which the same species is simultaneously oxidised and reduced Example of a disproportion reacti...
Edexcel A Level Chemistry:复习笔记2.1.2 Types of Reduction & Oxidation
Electron Transfer & Change in Oxidation Number Oxidation and reduction in a reaction can be demonstrated in terms of electron transfer For example: 2NH3 + 3Br2 → N2 + 6HBr The oxidation ...
Edexcel A Level Chemistry:复习笔记2.1.1 Oxidation Number
Defining Oxidation Number There are three definitions of oxidation and reduction used in different branches of chemistry Oxidation and reduction can be used to describe any of the following...
2023年全美最佳大学排名表最新发布！
世界专业排名机构之一U.S.News&WorldReport《美国新闻与世界报道》（下面简称U.S.News）官方网站公开发布了2023年全美最佳大学排名表最新排名！ 1，排名指数 排名的因素以及权重与去年基本一致，只是在细分的...
