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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

請問第16、17要怎麼作答

It's widely known that bees are important for our ecosystem and that they are facing increasing threats from modern agricultural practices involving pesticides. What many of us don't know, 16. (is that some industries should shoulder a bigger share of blame than they're given.) The almond industry, for instance, has quite an adverse impact on bee colonies. One potential harm to bee colonies is the stress caused by transporting them over long distances to almond orchards for the task of pollination. This transportation can be stressful for the bees, hence 17. them more vulnerable to diseases and pests. Moreover, since they're 18. having limited food sources aside from almond flowers further weakens bee colonies. Still another problem is the of honeybees to pesticides and other chemicals used in almond production. 19. 20. and One sustainable solution is to make habitats and species within almond orchards more stable. By creating various ecosystems and introducing other insects among almond trees, at least we can ensure enough food supply for bees and even lower the use of pesticides for almond trees in the long run. A 16. (A) therefore (B) however C17. (A) make A (B) made 18. (A) faced with a great increase in demand (C) looked after by beekeepers carefully (B) delivery 19. (A) cultivation 2 (C) in addition (D) for a start (C) making (D) to make (B) raised in their natural environment (D) physically removed from their habitat (C) exposure (D) restriction asant (D) particular

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英文 國中

這邊想請問一下在底線處中into just的作用以及翻譯中的我們從何而來>_<翻譯是這讓我們洞悉他多年來有多受歡迎以及多具影響力

............. LEUTELZ 2 queen (A) engaged N 詞彙磨刀石 好奇到 Xidl basis 1. The public wondered how much the mysterious gentleman was the secret government mission. (B) permitted 2. The smartphone brought about oprio (A) luxurious (B) grammatical ...**** 3. The poet's lines are beautiful and filled with human experience. (A) session (B) auction 第2關 (C) conventional 詳答參見詳解本 P (C) impressed changes in our lifestyles. (C) insight (D) transported (D) revolutionary and knowledge of the (D) therapy 建議作答時間 5 分鐘 分鐘 實際完成時間 the sh the te thora of ne gian mar 閱讀擂臺 svo of youmici bu code Joodse vlamhsa asiat od 1 Jengganap ni slo Gundam is a science-fiction franchise of television shows, movies, novels, comics, evalg quoz ns.1 and video games that features giant robots called "mobile suits." The franchise started umpasy drow ai dood zidi ydw 210bar di 16] with the broadcast of an anime television series called Mobile Suit Gundam in 1979. It was so popular and revolutionary that it created a new genre, a type of show that of .. features giant robots in a military setting. The franchise has been called the Star Trek of Japan, which gives some insight into just how popular and influential it has been over the years. do Yoshiyuki Tomino was the principal creator of the first series, Mobile Suit Gundam, and remains largely in charge of the entire franchise, writing and directing the 2014 television series, Gundam Reconguista in G. The name "Gundam" is a combination of the words "gun" and "dam," although originally, the show was called Gundom, from "gun" and "freedom." The stars of the franchise, the giant robots themselves, are large bipedal, human-shaped vehicles controlled from a cockpit, which is usually located in upper body of the machines. 2 the T

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