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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 高中

想問此大題的第6小題的用法

acher solved to recall. ton certain. his wife. ted by da the d 五、綜合測驗:10% > 大量的維修 Lesson 3 In 1822-1823, Lin Chi-neng built a beautiful home in Taipei/He named the Lin An Tai, taking "An" from Anxi, his father's hometown, and "Tai" from his company's and it was 2. name. One hundred and fifty-five years later, the Lin family no longer lived in the house, and city planners decided the house should be torn down. considerable repairs. It was a time a A number of scholars wanted to save the house a 6. 3. the city was expanding, 4. being destroyed They started to persuade the authorities not to tear it down. Thanks to their efforts, there was project to relocate* the house. At first, they didn't know they chose a park beside the Keelung River in Zhongshan District. 7., but eventually 8. it took the city twenty-two years to move the house piece by piece and then rebuild it at the new location 9. It was crucial that they exactly the same way. mak After being moved, the home was transformed to the public in 2000. where every piece was so that they could rebuild the house won ji 919rw of aistom nosinsvar ond saundidgil 10. bovora ya a museum which was open Juods adid Oday, it is considered the best-maintained example of a traditional Of D980 19gnor off al 92090 building in Taipei. DINO (99 уBM Jasoo ayos adi no hembral inshoq me aniamen 註:expand 擴張 relocate 搬遷 VEDOI bns 29rvont be awoda VT 2009 ni boutest mosd and af A) 1.(A) residence 2. (A) at risk of 3. (A) where (D) 4. (A) against (5. (A) glimpse (B) mission (C) progress 需要 of (B) in a bad (B) which (B) upon (C) at the cost of f .01 (D) transportation xel (D) in honor of (C) when (D) what (C) under (D) from (B) conclusion (C) replacement (D) campaign (B) led-government (A) (B) where they should put it woH (8) zoq ai i 6. (A) leading-government uaisi tot asw gribi (D) government-leading (C) government-led 7.(A) should they put it where ne wan badi (C) where should they put it AB 8. (A) All in all (D) they should put it where 329) 畢竟 (B) After all iga (C) In the meantimed bus alihs ((D) Once upon a time 9.(A) recorded to give the carefully tak (B) record 2 BA was (C) were recording C10. 10. (A) by ld a dived (B) from (D) have recorded (C) into wen sit bre 162 Ji 15A (C) ced the 80 to the 課 is still displayed today Karl fanx Your (D) with ohioriigil all griauty thudiar book that S+ (should) + AU. bis adj it is to you gone to see od sol Molur *leinoloo sang 1970 loquos

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英文 國中

求解 急 怎麼看都不順眼 第29

,我穿起來很漂亮 24 (A) It looks pretty on me. (C) Whe can 1 it on? ) 25. (A) It's expensive. (B) (C) It is too small to wear. 991473 (B) How much is it? (D) Is it my size?這是我的嗎 (B) I'll take this one. (D) I don't like it, either. (1) 26. (A) How much money do you have? (B) Isn't it expensive? (C) Do you have credit cards? (D) How would you like to pay? [31 【27~29】 27 Basketball has been around for more than one hundred years. It 18 C was invented in 1891 by James Naismith, a PE teacher, who tried hard to think of a game for his students to play inside on a rainy or cold winter day. A Naismith wrote some basic rules and used a peach basket for players to throw a ball in. At that time a soccer ball was used to play in the game. Quite different from modern basketball games, the first அ ones in history were slow because there were no holes in the bottom of the peach baskets. When a player threw a ball in a peach basket, the ball stayed there. The game had to stop so that one of the players could climb up to get the ball. Although the first basketball games seem funny, they were an important start of one of the most popular sports in the world. invent 創造 basic 基本的 k C a p y le li a 11 seem 似乎 n (7) 27. What is the best title for the reading? title 標題 (A) James Naismith (B) PE Classes (C) Sports and Their Rules (D) The History of Basketball 28. What CAN'T we learn from the reading? B (A) The first basketball baskets. (B) The number of players on each team. (C) James Naismith's job. (D) Why James Naismith invented basketball. (B) 29. Which of the following usually has a hole in its bottom? (A) A couch. (B) A mat. 長椅 墊 【30~32] (C) A pot. (D) A tub. |tub 浴缸 Dear Sarah, I have two tickets for the game between the Elephants and the Lions next Tuesday. David said that he could go to the game with 21

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英文 高中

請問第4題為什麼選B?

2. 3. 4. 乃 jumping up and down. (Atoo; to (B) so; that (C) such; that (D) enough; to Eric took a walk in the neighborhood, he bumped into one of his former classmates. (A) As (B) Which (C) That (D) What ) I'll have a busy schedule tomorrow. If you need to reach me, I at this time A tomorrow, which means I'll not be available. (A) will have a meeting (B) am having a meeting would be holding a meeting (D) will be having a meeting ) Having a sense of responsibility makes Jack (A) to be a great class leader (B) a great class leader being a great class leader (D) as a great class leader 三、綜合測驗 1. In 1843, Henry Cole was a popular man. However, this popularity was causing him some trouble. Specifically, he received a lot of mail, sometimes so much that he didn't know (1)___ to reply to all of it in his free time. To solve this problem, he hired an artist named J. C. Horsley to draw a family____(2)____ was celebrating Christmas and then had this image printed one thousand times on postcards. On each card, there was also space to write a person's name and a short message. This is how the first commercial Christmas card was born. Did Cole know that Christmas cards would _(3)___ sit over the fireplaces* in so many houses? Probably not, but his friends quickly _(4)___ Christmas cards an annual tradition. Fast forward to 1873, and a man named Louis Prang had succeeded in making Christmas cards popular throughout the US. The front side of each of Prang's cards read "Merry Christmas, accompanied by an image of beautiful flowers or animals. In the late 1880s, many card companies were competing in 1915. when the Hall

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