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自然科學 大學

為什麼[A(org)]=n[An(org)]成立 (第三張圖equation 7.9) 感謝

Experiment 7 Experiment 7 The partition of Organic acid between Water and Organic solvent Objectives Understand the partition of a solute between two immiscible solvents. Introduction A chemical analysis that is performed primarily with the aid of volumetric glassware (e.g., pipets, burets, volumetric flasks) is called a volumetric analysis. For a volumetric analysis procedure, a known quantity or a carefully measured amount of one substance reacts with a to-be-determined amount of another substance with the reaction occurring in aqueous solution. The volumes of all solutions are carefully measured with volumetric glassware. The known amount of the substance for an analysis is generally measured and available in two ways: 1. As a primary standard: An accurate mass (and thus, moles) of a solid substance is measured on a balance, dissolved in water, and then reacted with the substance being analyzed. 2. As a standard solution: A measured number of moles of substance is present in a measured volume of solution - a solution of known concentration, generally expressed as the molar concentration (or molarity) of the substance. A measured volume of the standard solution then reacts with the substance being analyzed. The reaction of the known substance with the substance to be analyzed, occurring in aqueous solution, is generally conducted by a titration procedure. The titration procedure required a buret to dispense a liquid, called the titrant, into a flask containing the analyte. A reaction is complete when stoichiometric amounts of the reacting substances are combined. In a titration this is the stoichiometric point. In this experiment the stoichiometric point for the acid-base titration is detected using a phenolphthalein indicator. Phenolphthalein is colorless in an acidic solution but pink in a basic solution. The point in the titration at which the phenolphthalein changes color is called the endpoint of the indicator. Indicators are selected so that the stoichiometric point in the titration coincides (at approximately the same pH) with the endpoint of the indicator.

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英文 國中

我這樣寫對嗎👀👾(八上文法宅急便)

(A) 18 【小試一下] (一)填充題 1. Before he eats pizza, he will wash 2. When I save enough money, I will take 3. After Joe knows about the fact, he Will everything about it. (二)翻譯填空 1. 在他來這裡之前,我會等他。 I will wait for him 2. 嬰兒一歲時,我將買給她一份可愛的生日禮物。 When the baby is one year old, I (W) will gift for her. 3. 完成她的自然功課後,她將打電動一小時。 •練習 She'll play science homework. (一)依提示作答 video games for an hour his hands. a trip to Japan for a week, call me up and tell me (C) V before he Come here. (B) buy A a lovely birthd after she finisher A A B F David will have free time tonight. (用 When 開頭合併為一句 ) He will go to a concert with Anna. When David have free time, he will go to a concert with 2. After Jim washes his hands, he will eat the pizza. (Before 翻譯 Anna Toni Before Jim eats the pizza, he will wash his hands. 1. 今晚吃晚餐後,我和我太太將在公園散步。(Mywife... will.... will...) My wife and I will go for a walk at park after dinner. 2. 這個週末有空時,爸爸將幫忙我的數學功課。(Dad will help with...) Toni Dad will help with my math homework when he has frec 學力模擬演練 單題(每題5分,共75分) 1. Mr. and Mrs. Smith did not know much about Taiwan when they beautiful island. this weeken 得分 ( ( to the (A) came (C) are coming (B) come (D) comes

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英文 國中

我這樣寫對嗎👀👾(八上文法宅急便)

(2) 阡陌 (3) 三 (份) (3) (4) (份) (6) () I 14 ·練習 2. 起床後,Amanda 總是為她的家人煮早餐。 Amanda always Cook breakfast for her family wake up. 3. 早晨淋浴後,Roger 開車去上班。他總是精力充沛。 Roger gues He's always energetic. (一)依提示作答 2. 1. { to work after he after she touk a shower in the morning. Nora turned off the computer. (用... after... 合併為一句) She went to bed. Nora went to bed after she turned of the cumputer. Mom came home at 6:00p.m. The rain stopped at 6:30p.m. dr benior (用The rain 開頭合併為一句) The rain stopped after mom came home. 3. Alan / got up, / made the bed/.(用從屬連接詞開頭合併為一句) After Alan got up, he made the bed. blux 4. Megan did her math homework, and then she played computer games. (用 After 開頭改寫) (二)翻譯 After Megan did her math homework, she played computer games. 1. 吃完午餐後,他們喝了黑咖啡。(... after they....) They drank black coffee after they ate lunch. √ 2. 每天吃晚餐後,我不可以看太多電視或者打太多電動(After video). ... After dinner, I can't watch TV or play video too much. 二 從屬連接詞 before 從屬連接詞 Before 主詞 動詞.... 主詞 動詞.... he joined the club, dad he | was a poor swimmer. -附屬子句 odt tes ——主要句子 主詞 動詞... 從屬連接詞 主詞 動詞……… He was a poor swimmer before he joined the club. 主要句子. -附屬子句-

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