作者YapYap (never give up)
看板TransBioChem
標題[化學] 台大普化C(95&97) 普化B(96) 問題
時間Mon Jun 1 23:43:10 2009
先謝謝願意看我問題的人!
=普化(C)97年=
先分享我的選擇題答案
1.AD BC C B B
6.C C C A CD
11.A AD C C D
16.BD D D AC A
13.(a)CH3CH(NH2)COOH有geometric isomers嗎?
20.For the reaction at 25度C, 2NO2(g)<===>N2O4(g)
CalculateΔG of the reaction if P(NO2)=0.29atm, P(N2O4)=1.6atm
Compounds ΔHf°(kJ/mol) S°(J/mol-K) ΔGf°(kJ/mol)
-----------------------------------------------------------
NO2(g) 33.84 240.5 51.84
N2O4(g) 9.66 304.3 98.28
(a)-5.04kJ (b)1.90kJ (c)46.44kJ (d)-1.17kJ
我的算法是98.28-2x51.84=-5.40kJ，選(a)
但是看到上面板友分享的答案是(b)
再加上我也覺得我的算法怪怪的，之前看到的這種題目好像都是單向反應，可是這題
是可逆反應，不知道算法一樣嗎? 然後題目提供的壓力、ΔH、ΔS我也都沒用到...
=普化(B)96年=
II.3.Consider the Harber process, 1/2N2(g)+3/2H2(g)->NH3(g) at 25°C
(a)Calculate the ΔH°,ΔS°,and ΔG°for the reaction.
(e)How is the rate of the reaction, fast or slow?
N2(g) H2(g) NH3(g)
-------------------------------------------
ΔHf°(kJ/mol) -46.19
S° (J/mol.K) 191.50 130.58 192.5
ΔGf°(kJ/mol) -16.66
我的算法:ΔH°= -46.19-(0+0)=-46.19
S°=192.5-(1/2x191.5+3/2X130.5)=-99.12
ΔGf°我想用ΔH°-TΔS°來算，可是驗證題目有給的NH3的資料
-46.19-298x192.5x/1000=-103.56，並不等於-16.66阿@@
=普化(C)95年=
分享我的答案 1.BACAC 6.CCBBD 11.ECBCB 16.DCACC
10.(d)At constant pressure and temperature, a decrease in free energy ensures
an increase in entropy of the system.
請問(d)選項是對的嗎?
II.3.Consider an ionic compound CxAy where the anions(A) are in a body-centered
cubic arrangement and the cations(C) are located in all of the faces of the
cubic unic cell.
(a)What is the empirical formula of the salt?
(b)If the edge length of the unit cell is 5.00x10 cm and the molar masses of
C and A are 50.0g/mol and 100.0g/mol, respectively,calculate the density
of CxAy.
(c)If the ionic radius of A is 200pm, estimate the ionic radius of C(in the
unit of pm).
我想問的是"cations(C) are located in all of the faces of thecubic unic cell"
這句話是指單位晶格每個面的中心都有一顆C嗎?
如果是這樣子我算出來的答案是(a)C3A2 (b)4.67x10^-27 不知道對不對?
然後(c)還是不會
希望有人能替我解答!麻煩大家了!
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