2022马歇尔经济学会写作比赛题目已公布，新赛季报名开启！
马歇尔学会是剑桥大学的经济学会，马歇尔经济学会写作比赛（Marshall Society Essay Competition）是面向A-level、IB和其他体系学生打造的写作比赛，要求学生利用现实世界的相关论据对经济理论进行充分解释和合理...
AQA A Level Chemistry复习笔记2.2.4 Uses of Group 2 Elements
Uses of Group 2 Three different calcium compounds are used commonly in agriculture, construction and iron extraction: Limestone - this is impure calcium carbonate Quicklime - this is calcium...
AQA A Level Chemistry复习笔记2.2.3 Reactions of Group 2
Reactions of Group 2 The group 2 elements react with oxygen, water and dilute acids Group 2 Reactions - Observations Reactions with water and oxygen The reaction of group 2 metals wit...
AQA A Level Chemistry复习笔记2.2.2 Solubility of Group 2 Compounds: Hydroxides & Sulfates
Solubility of 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 ...
CollegeBoard发布SAT机考样题，正式回应黄牛考位问题
今天，CollegeBoard正式放出了SAT机考样题，并采取直播方式对机考模式进行讲解，同时，首次正面回应了黄牛考位问题，小编一起来和大家分享下。 在今年1月份，CB宣布SAT进入机考时代，国际考场在2023年春季率先使...
AQA A Level Chemistry复习笔记2.1.4 Trends of Period 3 Elements: Melting Point
Trend: Melting Point Melting points of the elements across period 3 A pattern is a little harder to see from the data, but you can see that it rises and falls: Melting points of the period 3...
AQA A Level Chemistry复习笔记2.1.3 Trends of Period 3 Elements: First Ionisation Energy
Trend: First Ionisation Energy The first ionisation energy (IE1) is the energy required to remove one mole of electrons from one mole of atoms of an element in the gaseous state to form one ...
AQA A Level Chemistry复习笔记2.1.2 Trends of Period 3 Elements: Atomic Radius
Trend: Atomic Radius Elements in the periodic table are arranged in order of increasing atomic number and placed in vertical columns (groups) and horizontal rows (periods) The elements acros...
AQA A Level Chemistry复习笔记1.9.3 Redox Equations
Balancing Redox Reactions Balancing equations using redox principles is a useful skill and is best illustrated by following an example It is important to follow a methodical step-by-step app...
AQA A Level Chemistry复习笔记1.9.2 Oxidation States: The Rules
Oxidation States Oxidation State Rules A few simple rules help guide you through the process of determining the oxidation state of any element Remember, you are determining the oxidation sta...
AQA A Level Chemistry复习笔记1.8.5 Changes Which Affect the Equilibrium
Changes Affecting the Equilibrium Constant Changes in concentration If all other conditions stay the same, the equilibrium constant Kc is not affected by any changes in concentration of the ...
AQA A Level Chemistry复习笔记1.8.4 Calculations Involving the Equilibrium Constant
Kc Calculations Calculations involving Kc In the equilibrium expression each figure within a square bracket represents the concentration in mol dm-3 The units of Kc therefore depend on the f...
