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[問題] CHEM 3Q help!

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CHEM 3Q help!

Q1:mole ratio 唔係2:1咩?
Q2:acet- 係咩functional group ?為什麼答案係C?
Q3:我想問係咩reaction?

thx!
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第一題
我建議你唔好好似marking  咁做..因為marking 省略左好多steps
而且 問題係問hydroxide ion ..  Ca(OH)2 >>Ca2+   + 2OH-
1個mole ge Ca(OH)2 會有2個mole ge hydroxide ion

所以我清楚d 咁計出黎
2HCl +Ca(OH)2 >>CaCl2 + 2H2O
no. of mol of Ca(OH)2 reacted = 0.1 * 9.1 *10^(-3) * 0.5 =4.55x10^(-4)

Ca(OH)2 >>Ca2+   + 2OH-
1個mole ge Ca(OH)2 會有2個mole ge hydroxide ion
concentration of OH- in the saturated solution =  4.55 * 10^(-4) * 2 / (20*10^-3)= 0.0455 mol dm^(-3)

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第二題
acteyl group 係functional group >指緊CH3 CO ---R
A. wrong >>no neutralization effect with hydrochloric acid released from stomach
B. wrong >> in order to rotate polarized light in in the polarimeter..it should possess a chiral carbon centre
D. wrong >>its chemical name is acetylsalicyclic acid >  salicyclic acid refers to 2-hydroxylbenzoic acid

so C is only one that is not eliminated
Further confirmatory explaination of option C
C. correct >>it undergoes alkaline hydrolysis with heated with NaOH to give RCOO- and ROH

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第三題

e個係一個halogeno compound 加OH-
因為有埋reflux ...所以有兩個不同的reaction 出現..出左個兩隻product with different percentage of yield
個兩個reaction 係nucleophilic substitution同埋elimination

for nucleopilic substitution ..個Br- 俾OH- sub 走左>>自己數番d no. of atom >>C10H15ON

for elimination Br ...H  are eliminated to form C10H13N
C10H13N >>H2NCH=C(CH3)CH2 (C5H6)

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