作者kirarapon (我要吐了...............)
看板TransBioChem
标题[化学] 台大普化B (94.96)
时间Wed Jul 8 18:56:53 2009
=94年=
10. 42.0 ml of Pb(NO3)2(aq) solution react with 25.0 ml of 0.140M NaCl
solution.What is the molarity of the Pb(NO3)2(aq) solution?
(a)3.50*10^-3 M
(b)4.17*10^-2 M
(c)1.75*10^-3 M
13. 4 ice cubes are at 0.00度C,each with a volume of 1.00 in^3;How much
heat is needed to melt the ice cubes?Density of ice is 0.917 g/cm^3
and the heat of fusion of ice is 333 J/g*度C
(a)2.00*10^4 kJ
(b)2.00*10^4 cal
(c)2.00*10^4 J
(d)2.00*10^4 kcal
14. What is the wavelength of a radio station that broadcasts at a
frequency of 100.3 MHz?
(a)3.009*10^16 m
(b)3.000*10^8 m
(c)2.991 m
(d)5.001*10^2 m
29. Uranium reacts wuth fluoriue to produce a compound which is a gas
at 57度C .The density of this gas is 13.0 g/L at 7度C and 1 atm.
What is the molecular formula of this compound?
(a)UF2
(b)UF3
(c)UF4
(d)UF6
第14题在单位上有点问题，不晓得MHz是不是要乘以10的几次方？
29题U和F的原子量用235及19代入後答案是3.34，是舍去後面选3？还是有另外的解答方式
=96年=
10. At 63.5度C, the vapor pressure of H2O is 175 torr,and that of ethanol,
C2H5OH,is 400 torr. Assuming ideal-solution is formed by mixing equal
moles of H2O and C2H5OH at 63.5 度C.
(a)The mole fraction of ethanol in the solution is 0.500.
(b)The partial pressure of ethanol over the solution is 200torr
(c)The total vapor pressure of the solution is 575 torr
(d)The mole fraction of the ethanol in the vapor above the solution
is 0.500
以上是比较有问题的几题，试了几次都没办法做出正确答案，翻书也没得到解答
先感谢耐心看完的各位，也烦请会的版友帮忙解答一下，感谢！
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1F：→ zazion:10.由反应式得Pb:Na为1:2 故42*X =(1/2)*25*0.14 移项求得 07/09 21:43
2F：→ zazion:14. MHz = 10^6 Hz ||29. U用238代比较接近3我是这样XD 07/09 21:47
3F：→ zazion:13. 把in换成cm就可以了 应该XD 07/09 21:51
4F：推 za7550295566:96 10. 理想溶液 P=Pa*Xa+Pb*Xb 07/13 19:09
5F：→ za7550295566:所以BC不对 07/13 19:09
6F：→ za7550295566:xb=Pb*Xb/P 所以选A? 07/13 19:10
7F：→ za7550295566:还有铀的主要分子量是238 235占少数 07/13 19:12
8F：→ za7550295566:Xb 溶液中的莫耳分率 xb 气相中的 07/13 19:14