將個notation改做delta h of reaction你就要識得計
計數以外既野應該唔洗
[DSE化學2019]同學準備好DSE CHEM未? (2)
化學艾維斯
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想再問下acidic/alkaline hydrolysis of acid/alkaline
我見past paper 係寫 naoh(aq) 咁或者用dilute acid, 咁係咪加concentrated acid/alkali 係唔得，一定用dilute
我見past paper 係寫 naoh(aq) 咁或者用dilute acid, 咁係咪加concentrated acid/alkali 係唔得，一定用dilute
同一樣野 指最高果支
sor更正 parent peak係指molecular ion peak
絕大部分情況係用non polar mobile phase
愈polar既substance會跟mobile phase號得愈快 higher Rf
愈polar既substance會跟mobile phase號得愈快 higher Rf
阿Sir 你係條片度mention嘅polarity同Rf value嘅關係係點？越polar嘅話會越soluble係stationery or mobile phase？？？絕大部分情況係用non polar mobile phase
愈non polar既substance會跟mobile phase跑得愈快 higher Rf
both ok
yes always size
yes always size
yes both ok
無話唔得 但一定會比足夠資料
睇下佢有無強調dry/pure solid
one only
由始至終都無in syl
考你識唔識諗
考你識唔識諗
唔好double 因為H+ concentration未必完全double 講快左ok
一般唔洗 evaporate solvent ok
yes correct
正常用dilute
阿sir colour change at end point 嗰度可唔可以解釋下 點解係pale yellow to pale pink?而唔係 pale green to purple?另外可唔可以示範下simple distillation set-up點畫？年年marking個set-up畫到咁仔細，但其實畫到咩程度已經可以拎足分？
見佢有啲要落drying agent 落個organic layer 到 咁係咪都係睇佢有冇寫dry？
咁係咪都係睇佢有冇寫dry？yes
saturated solution點解唔一定concentrated？
每隻野saturation個濃度都唔同 有d溶得少少既最後咪唔濃
當然 所謂concentrated其實無非常統一既說法 某隻solute saturated對佢本身黎講已係最conc
當然 所謂concentrated其實無非常統一既說法 某隻solute saturated對佢本身黎講已係最conc
Crystallisation 點解要warm gently 先obtain 到saturated solution?