最后一周！2022年紐約時報夏季讀寫比賽即將結束，速度報名！
2022《紐約時報》夏季讀寫比賽?? 報名即將截止！ 學術活動時間：2022年6月10日-8月19日 2022紐約時報夏季讀寫比賽? 自2010年起， 《紐約時報》每年夏天都會舉辦的夏季讀寫比賽，目前全球已有超過8萬名中學生參與...
CIE A Level Chemistry復習筆記3.4.1 Production of Alcohols
Production of Alcohols Alcohols?are compounds that contain at least one?hydroxy?(-OH) group The general formula of alcohols is?CnH2n+1OH Alcohols can be prepared by a wide range of chemical reactio...
CIE A Level Chemistry復習筆記3.3.5 Reactivity of Halogenoalkanes
Reactivity of Halogenoalkanes The halogenoalkanes have different?rates?of?substitution?reactions Since substitution reactions involve?breaking?the?carbon-halogen?bond the?bond?energies?can be used ...
CIE A Level Chemistry復習筆記3.3.4 SN1 & SN2
Halogenoalkanes: SN1 & SN2 Mechanisms In?nucleophilic substitution?reactions involving halogenoalkanes, the halogen atom is replaced by a nucleophile These reactions can occur in two different ...
CIE A Level Chemistry復習筆記3.3.3 Elimination Reactions of Halogenoalkanes
Halogenoalkanes: Elimination Reactions In an?elimination?reaction, an organic molecule loses a small molecule In the case of halogenoalkanes this small molecule is a hydrogen halide (eg. HCl) The h...
CIE A Level Chemistry復習筆記3.3.2 Substitution Reactions of Halogenoalkanes
Nucleophilic Substitution Reactions of Halogenoalkanes Halogenoalkanes?are much more reactive than alkanes due to the presence of the?electronegative?halogens The halogen-carbon bond is polar causi...
CIE A Level Chemistry復習筆記3.3.1 Production of Halogenoalkanes
Production of Halogenoalkanes: Substitution & Addition Reactions Halogenoalkanes?are alkanes that have one or more halogens They can be produced from: Free-radical substitution?of?alkanes Elect...
CIE A Level Chemistry復習筆記3.2.11 Markovnikov's Rule
Alkenes: Stability of Cations & Markovnikov's Rule Carbocations?are positively charged carbon atoms with only three covalent bonds instead of four There are three types of carbocations: primary...
CIE A Level Chemistry復習筆記3.2.10 Electrophilic Addition of Alkenes
Alkenes: Electrophilic Addition The double bond in alkenes is an area of high electron density (there are four electrons found in this double bond) This makes the double bond susceptible to attack ...
2022劍橋TMUA數學考試介紹，哪些學校和專業需要TMUA？
TMUA這兩年突然“異軍突起”，先是2021年劍橋宣布所有申請計算機科學的學生都要考 TMUA；再是今年劍橋砍掉 ECAA，改為 TMUA。可以說 TMUA 是這兩年劍橋最重視的考試了！連LSE 都官網鼓勵申請學生考TMUA。為什么TMUA...
CIE A Level Chemistry復習筆記3.2.9 Test for Unsaturation
Test for Unsaturation Halogens can be used to test if a molecule is?unsaturated?(i.e. contains a double bond) Br2(aq) is an orange or yellow solution, called?bromine water?and this is the halogen m...
CIE A Level Chemistry復習筆記3.2.8 Reactions of Alkenes
Reactions of Alkenes Alkenes are very useful compounds as they can undergo many types of reactions They can therefore be used as starting molecules when making new compounds Electrophilic addition ...
