Revision: Age Structure There are 3 basic age structures: 1. Progressive (Brazilian) Type 2. Stationery (American) Type 3. Regressive (European) Type Progressive Type It has a wide base that quickly narrows upwards to a point. It indicates a large birth rate, but poor conditions mean people rapidly die off, hence the triangular shape of the structure. The population is increasing. Stationery Type The shape of this structure is more square. All ag

Revision: Britain (1815-1841) Prime Ministers William Pitt: 1783-1801, 1804-1806 Henry Addington: 1801-04 Lord Grenville: 1806-1807 Duke of Portland: 1807-1809 Spencer Perceval: 1809-1812 Lord Liverpool: 1812-1827 George Canning: 1827 Viscount Goderich: 1827-28 Duke of Wellington: 1828-1830 Earl Grey: 1830-1834 Lord Melbourne: 1834, 1835-1841 Sir Robert Peel: 1834-1835, 1841-1846 Chartists Thomas Attwood William Benbow George Binns John Cleave Th

Revision: Demand Theory A demand curve For the vast majority of goods, when a good falls in price more people buy it. This is because they are gaining consumer surplus. The market demand consists of the sum of all effective demand of households. The demand curve is downward sloping because when the price falls, the quantity demanded increases. Determinates of demand The following factors may influence demand, shifting the demand curve to the left

Revision: Contestable markets The theory of contestable markets states than in imperfect markets, the threat of competition may be enough to prevent the firm acting against the public interest (i.e. keeping prices high and output low). Conditions for contestable markets: 1. Perfect information - all firms have the same access to technology, no patents etc. 2. Freedom to enter the market legally 3. No sunk costs In contestable markets incumbent fi

Revision: Economic Rent and Transfer Earnings Transfer earnings are the minimum payment required to keep a factor of production in its present use. It is the opportunity cost an individual forgoes when deciding to work in one job rather than the next best alternative. Example - a man may decide to work as a shop assistant because they pay is better than if he was a waiter. By making this decision he forgoes the opportunity to work at, for example

Edexcel 化学 The Core Principles of Chemistry part: 章节主要内容计划课时 Chapter 1Formulae, equations and amounts of substance4 h Chapter 2Energetics6 h Chapter 3Atomic structure and the periodic table4 h Chapter 4Bonding4 h Chapter 5Introductory organic chemistry4 h past paper真题讲解如果是即将参加考试，讲解past paper时间约分配为8 hour8 h 课时合计学生科根据具体章节选择上课内容30h Edexcel 化学

A LEVEL的考试是知识性很强，相比国内的高考，其需要理解记忆的东西更多。在考试的时候，Alevel的考题偶尔会比较长的，有很多干扰性的内容或者是很多知识性的内容，尤其对于英语差一些的同学，读起来就很困难，而且还要在一个小时内做完40个multiple choice就有些难上加难了实际上，我们在考试的时候，题目中的很多内容，我们只要部分读

Revision: Structure and Bonding Ionic bonding Ionic bonds are a type of chemical bond based on electrostatic forces between two oppositely-charged ions. In ionic bond formation, a metal donates an electron, due to a low electronegativity to form a positive ion or cation. Often ionic bonds form between metals and non-metals. The non-metal atom has an electron configuration just short of a noble gas structure. They have high electronegativity, and

Revision: Halogens Trends in chemical properties chlorine will displace bromine and iodine bromine will displace iodine but not chlorine iodine will displace neither chlorine or bromine Oxidizing Power F2Cl2Br2I2 Reactions with Cl2 Reactions with Br2 Reactions with I2 Trend in electronegativity decreases as atomic number increases Trend in boiling point all exist as diatomic molecules attraction = weak intermolecular forces van der Waals forces i

Revision: Anaerobic Respiration Glycolysis glucose molecule 2 molecules of ATP (4 created-2 used) 2 molecules of NAD+ reduced to 2NAD +2H+ (transferred to electron transport system). 2 molecules of pyruvate 2x3carbons (they enter Link Reaction) Link Reaction Pyruvate Oxidation Occurs in the matrix of mitochondria. Pyruvate combines with coenzyme A to form acetyl coenzyme A. In the process a molecule of CO2 and 2H are removed. The hydrogen atoms a