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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)

-練習· (一)依提示作答 Unit 2 You Can Learn About Game Design After You Join the Club 17 4. Dora goes to the movies. 1 (用When 開頭合併為一句) She has free time. When Dora has free time, she goes to the movies. Be careful. 2 (用When 開頭合併為一句) You walk home at night. (二)翻譯 ji tuods gnuiry When you walk home at night, be careful. Dylan needed some help. He called his mom. (用... when... 合併為一句) Dylan called his mom when he needed some help. Carol reads. She always listens to music. (用... when... 合併為一句) always listens to music when she reads 1.天氣炎熱時,他的孩子們吃很多冰淇淋。(When the...) When the weather is hot, his kids eat a lot of ice cream. 2. Zoey 有錢和空間時間時,她去日本旅行。(Zoey.... Zoey travels to Japan when she has money and free time. 四 延伸補充巧肥 onpa用) aid zodauw coul 主詞 現在式動詞...+未來時間, 主詞 未來式動詞..... 從屬連接詞 After Before Ted visits Tainan tomorrow, he will call me. When ·附屬子句- 主要句子 文法說明 屬子句中的動詞,若在未來時間發生,不可用未來式動詞(助動詞 will<將>+原形 be / , 須用現在簡單式代替之,否定時則利用be/do/does+not 即可。主要句子中的動詞則 用未來式動詞。 Ⅲ: Sara will clean up the house when she isn't busy next Sunday. ·附屬子句用現在簡單式 (下星期日不忙時,Sara 會打掃屋子。) ▶主要句子用助動詞未來式 : Refore Jeff doesn't help me, I will do it on my own.

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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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