Reducing Errors Random errors can be reduced by repeated trials and measurements Multiple measurements when averaged will reduce the impact of a random error on the average The more readings you ha...
Types of Errors An error is the difference between a value or quantity obtained in an experiment and an accepted or literature value for an experiment There are two types of errors in experiments, ...
Qualitative & Quantitative data When recording results of experiment, both quantitative and qualitative data should be obtained Quantitative data is obtained from measurements whereas qualitati...
How IR Spectroscopy works All covalent bonds act rather like springs, as opposed to rigid bars Like springs, the bonds can vibrate in a number of different ways The frequency of vibration occurs in...
How NMR works Nuclear Magnetic Resonance (NMR) spectroscopy is used for analysing organic compounds Only atoms with odd mass numbers show signals on NMR spectra and have the property of nuclear spi...
Determining Molecular Mass When a compound is analysed in a mass spectrometer, vaporised molecules are bombarded with a beam of high-speed electrons These knock off an electron from some of the mol...
Index of Hydrogen Deficiency The degree of unsaturation or index of hydrogen deficiency provides information about the number of double or triple bonds in a molecule The IHD is the number of hydrog...
Reactions of Benzene Arenes are very stable compounds due to the delocalisation of π electrons in the ring This is because the electron density is spread out over the molecule instead of being conf...
Reactions of Halogenoalkanes Halogenoalkanes are much more reactive than alkanes due to the presence of the electronegative halogens The halogen-carbon bond is polar causing the carbon to carry a p...
Esterification Esters are compounds with an -COOR functional group and are characterised by their sweet and fruity smells They are prepared from the condensation reaction between a carboxylic acid ...
马上进入7月，2025Fall的同学们忙着为接下来的秋季入学做准备，2026、2027Fall的同学也逐渐进入申请前的“冲刺阶段”，大家想在有限的时间里，努力提升自己的竞争力，争取早日圆梦翠鹿！ 今年我们的学员再创佳绩，...
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