作者water0bearer (霖)
看板TransBioChem
标题Re: [化学] 99台联大A1 19 20
时间Sat Aug 7 00:57:18 2010
※ 引述《asd789456123 (123)》之铭言：
: 19.How many mmoles of HCL must be added to 100ml of a 0.10M solution of
: methylamine(pKb=3.36)to give a buffer having a PH of 10?
: (A)8.1 (B)18.7 (C)20.0 (D)41.5 (E)12.7
: Ans:(A)8.1
pOH = pKb + log[HA]/[A-]
4 = 3.36 + log[HA]/[A-]
log[HA]/[A-] = 0.64
[HA]/[A-] = 4.2(懒的按计算机，自己估计的)
CH3NH2 + HCl ---> CH3NH3+ + Cl-
0.1*100 = 10mmole 原来CH3NH2的量
设加入Xmmole
X / (10-X) = 4.2
X差不多=8.1
: 20.Of energy, work, enthalpy, and heat, how many are stable functions?
^^^^^^ ^^^^^^^^这两个 ^state吧!?
: (A)0 (B)1 (C)2 (D)3 (E)4
: Ans:(C)2
: 请问是哪两个呢? 感激不尽
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※ 发信站: 批踢踢实业坊(ptt.cc)
◆ From: 220.136.185.78
1F：推 BIEGABOY:state function是energy和enthalpy喔!! 08/07 08:45
2F：→ BIEGABOY:work heat是path function 08/07 08:47
3F：→ mensen:大一所学的状态函数只有两个 其实记一下无妨 08/07 16:45
4F：→ mensen:状态函数是和路径无关的函数 所以q和w就不是状态函数 08/07 16:47
※ 编辑: water0bearer 来自: 114.45.172.29 (08/07 21:10)
5F：→ water0bearer:我犯了大错~抱歉~写的和心里想的不一样...... 08/07 21:11
6F：→ asd789456123:谢谢 08/07 23:50