作者kirarapon (我要吐了...............)
看板TransBioChem
標題[化學] 台大普化B (94.96)
時間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題在單位上有點問題，不曉得MHz是不是要乘以10的幾次方？
29題U和F的原子量用235及19代入後答案是3.34，是捨去後面選3？還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
以上是比較有問題的幾題，試了幾次都沒辦法做出正確答案，翻書也沒得到解答
先感謝耐心看完的各位，也煩請會的版友幫忙解答一下，感謝！
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1F：→ zazion:10.由反應式得Pb:Na為1:2 故42*X =(1/2)*25*0.14 移項求得 07/09 21:43
2F：→ zazion:14. MHz = 10^6 Hz ||29. U用238代比較接近3我是這樣XD 07/09 21:47
3F：→ zazion:13. 把in換成cm就可以了 應該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不對 07/13 19:09
6F：→ za7550295566:xb=Pb*Xb/P 所以選A? 07/13 19:10
7F：→ za7550295566:還有鈾的主要分子量是238 235佔少數 07/13 19:12
8F：→ za7550295566:Xb 溶液中的莫耳分率 xb 氣相中的 07/13 19:14