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看板TransBioChem作者 (Vic)時間15年前 (2010/07/07 01:29), 編輯推噓3(301)
留言4則, 1人參與, 最新討論串1/1
1) The freezing point of 4.6 g of formic acid (HCOOH) dissolved in 1.0 kg of benzene (C6H6) is depressed by 0.26 oC, whereas that for the same amount of HCOOH dissolved in 1.0 kg of water is lowered by 0.19oC. (Kf , C6H6 = 5.12 oC kg/mol; Kf H2O = 1.86 oC kg/mol) In order to explain these observations, one need to assume that HCOOH is A) associated in C6H6 in monomeric in water. B) monomeric in C6H6 and associated in water. C) associated in C6H6 and dissociated in water. D) dissoiciated in C6H6 and monomeric in water. E) monomeric in C6H6 and dissociated in water. F) none of the above 看不太懂 題目的意思 可以請問 再問甚麼嘛 2) Balance the reaction below in acidic solution. IO3- + I- -> I2 What volume of 0.352 M HCl is needed to produce 2.48 x 10-3 moles of iodine, I2, with an excess of KIO3 and KI? (a) 2.48 mL (b) 4.96 mL (c) 7.05 mL (d) 14.1 mL (e) none of these 以下是我的算試 6HCl + KIO3 + 5KI -> 3I2 + 3H2O + 6KCl V X 0.352 = 2.48X10 負3 算出來的V 要X2嗎? 還是我想錯了 感謝 -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 111.248.5.141

07/07 01:32, , 1F
associated=變少 monomeric=不變 dissoiciated=變多 看i值
07/07 01:32, 1F

07/07 01:33, , 2F
i>1就是變多 i=1就是不變 i<1就是變少
07/07 01:33, 2F

07/07 01:36, , 3F
不是0.352*V 是0.352/2V = 2.48*10^-3
07/07 01:36, 3F

07/07 01:45, , 4F
是乘沒錯 我看錯單位了 > <
07/07 01:45, 4F
文章代碼(AID): #1CCsVjAY (TransBioChem)