作者shadowlin (我是球球的女朋友)
看板TransBioChem
标题[化学] 97年成大普化考古题
时间Thu Jul 2 09:49:57 2009
1. 13 12
Calculate the number of stages needed to change a mixture of CO2 and CO2
13 13
that is originally 0.10%(by moles) CO2 to a mixture that is 0.010% CO2 by
13
a gaseous diffusion process .(The mass of C is 13.003355 amu)
(A)205
(B)120
(C)365
(D)620
(E)435
2.
For the titration of 25 ml of 0.1M Na2CO3 with 0.1M HCl
(a)Calculate the PH after 50 ml HCl has been added
3.A student titrates an unknown weak acid,HA,to a pale pink phenolphalein
endpoint with 25 ml of 0.1M NaOH .The PH of the resulting solution is 4.7
Which of the following is true?
(a)the PKa of the acid is greater than 4.7
(b)the PKa of the acid is less than 4.7
(c)the PKa of the acid is 4.7
_
(d)At PH 4.7,half the conjugate base ,A , has been converted to HA
拜托大家教我了,想了好久,都还是不会
谢谢大家了!!
--
※ 发信站: 批踢踢实业坊(ptt.cc)
◆ From: 122.125.162.13
※ shadowlin:转录至看板 Chemistry 07/02 11:48
1F：推 ki16:第二题 有ka或kb值就算的出来了吧 07/04 21:03
2F：→ ki16:第三题我不确定 但我猜B 你参考看看罗 07/04 21:04