2023年AP考试报名工作正式启动，美国前30大学对AP成绩有何要求？
美国大学先修课程（Advanced Placement），简称AP课程，是由美国大学理事会（The College Board）在高中阶段开设的具有大学水平的课程，主要适合计划在美国就读本科的高中生学习，在全世界范围内（包括美国本土）...
Edexcel A Level Chemistry:复习笔记8.2.3 A-Level Qualitative Analysis
Core Practical 15: Analysis of Inorganic and Organic Unknowns Testing for positive ions Simple test tube reactions can be done to identify the following positive ions: Group 2 ions (M2+) Amm...
Edexcel A Level Chemistry:复习笔记8.2.2 Transition Metal Complexes
Core Practical 12: Preparing a Transition Metal Complex Method Weigh between 1.4 g and 1.6 g of copper(II) sulfate. To do this you should weigh a test tube and record its mass. Then add the ...
Edexcel A Level Chemistry:复习笔记8.2.1 Redox Titration
Core Practical 11: Redox Titration Redox Titrations In a titration, the concentration of a solution is determined by titrating with a solution of known concentration. In redox titrations, an...
Edexcel A Level Chemistry:复习笔记8.1.4 Activation Energy
Core Practical 14: Finding the Activation Energy of a Reaction In this practical the activation energy for the reaction between bromide ions and bromate(V) ions will be determined BrO3- + 5B...
Edexcel A Level Chemistry:复习笔记8.1.3 Rates of Reaction
Core Practical 13a: Titrimetric Methods The reaction between iodine in an acidic solution and propanone is CH3COCH3 (aq) + I2 (aq) → CH3COCH2I (aq) + H+ (aq) + I- (aq) We can follow the rate...
Edexcel A Level Chemistry:复习笔记8.1.2 Electrochemical Cells
Core Practical 10: Investigating Electrochemical Cells Measuring the EMF of a cell To measure a cell EMF you will need Two small beakers, around 75 cm3 capacity Strips of suitable metals suc...
Edexcel A Level Chemistry:复习笔记8.1.1 Finding Ka Values
Core Practical 9: Finding Ka for a Weak Acid The Ka of a weak acid may be determined by finding the pH at the half equivalence point At the half equivalence point Ka = [H+] Key steps in the ...
Edexcel A Level Chemistry:复习笔记7.7.5 Other Chromatography
Types of Column Chromatography Column Chromatography In column chromatography, the column is often a long vertical glass tube or in the laboratory a burette is suitable An inert solid (usual...
