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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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地理 高中

有沒有人能教我🥹 #1方位判讀 #2地圖投影 拜託了各位

羅盤方位法 A 在B的22.50 實例 A在B的北北東方 則B在A的202.50 則B在A的南南西方 (22.5°+180° 北 「B在A的 |南南西方 3.相對方位的判讀方法:已知A在B的某一方,判讀B在A的方位。 B在A的 象限角法 A 在B 的N22.5°E 則B在A的S22.5°W ACC 方位角法 = 202.5°) 0° 202.5° A ·90° 270° 西 /202.5° 相反方向為 | 相反方向 「南北互換, 南 |相差180° 180° 相反方向為 南北互換, 東西互換 225 圖示 東西互換 北 0° 1225° 度數不變 N. 1225° S W ● 90° 西 -東 270° B E B B A 在B 的 A在B的 |北北東方 南 A在B的 22.5° N22.5° E s 180° 重點停看聽 ● 由兩個已知目標來判斷觀測者在地圖上的位 置(圖2-7) 已知A在觀測者的S60°W,B在觀測者的 S40°E,在地圖上由A、B繪製出相對方位 線,也就是觀測者在A的N60°E,觀測者在 B的N40°W,而相對方位線在地圖上的交會 點,即為觀測者位置。 ▶ 圖2-7 由觀測點反推目標示意圖 60° W W A在觀測者的S60°W) B在觀測者的S40°E N 觀測者 E 60° 40° W. 40% 觀測者在A的N60°EN 「觀測者在B的N40 4.近年來,科技進步下,可以透過行動裝置或導航儀器,直接由全球導航衛星系統(GNSS 定位出使用者的座標,並進一步標示在有座標系統的地圖上。 知識補給站 球導航衛星系統(Global Navigation Satellite Systems 利用衛星訊號來提供全球定位服務的系统

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英文 高中

想問這幾題 想問為什麼錯的不能用+對的為什麼能這樣用?🙏

英文考科 二、綜合測驗(占10分) +3 on 說明:第11.題至第20.題,每題1分。 bodzowbred no 第11.至15.題為題組 In 1956, African honeybees were introduced into Brazil to improve honey production in the tropical climate of South America. However, they started to mix with European honeybees already living there and produced a new kind of "Africanized" honeybees that are better at setting up hiyes and at reproducing than European bees. Keeping Africanized bees poses a challenge to beekeepers. Generally, beekeepers keep their bees in 11. wooden boxes, or hives. s. Afte After the worker bees fill a hive with honey, the beekeepers open the lid of the hive and blow a few puffs of thick, cool smoke into the hive to help calm 12. easier to collect the honey. the bees, 第 2 頁 共 10 頁 The problem with keeping Africanized bees is that they are more defensive than European bees. Even the slightest bump against the hive may 13. an alarm. A large quantity of smoke is needed to calm the bees. Two or three beekeepers may need to work together to safely harvest the honey. And they may need to wear heavier beekeeping suits even in hot, 14. weather. Beekeepers may also collect less honey from Africanized bee hives. European bees form search parties and work together to collect flower nectar from which honey is made, while Africanized bees usually work alone in search of flowers. Therefore, less nectar is brought back to Africanized bee hives. Africanized bees also spend less time storing honey but more time caring for young bees. That may be because they 15. in a tropical climate where not much honey is needed for food during the winter. (C) starved AB 11. (A) stacked door Lyc (B) stuffed obl (A) which make them (B) so that they are (C) thus it would be D (B) go off (C) call off (A) get off (D) staffed (D) making it DLL CC

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英文 高中

英文問題 may not be什麼意思 感覺題目詳解給錯了

第 48 至 51 題為題組 Many of us have probably experienced déjà vu at least a few times in our life. Its meaning comes from the phrase "already seen" in French, and occurs when we feel that a person, place, or thing is familiar to us without actually having experienced them before. This strange phenomenon happens to as much as 70 percent of the population, but a higher number of 15 to 25 year olds experience it than any other age group. Maybe you just travelled to a new foreign country, and it just felt very familiar to you. Yes, you are feeling déjà vu; however, you know you haven't been there before. While different people experience déjà vu in different ways, it is still a pretty mysterious phenomenon, and researchers are putting the pieces together. Based on some studies, déjà vu is just a part of having a healthy memory checking system, and people who experience déjà vu more often are less likely to forget the details of important events. In fact, the results of the study don't look too promising in terms of mental health for people who never experience déjà vu. Scientists believe déjà vu is created by a neurological anomaly related to an improper electrical discharge in the brain. In short, it's not a mystical prophecy or out-of-body experience, but just your brain playing a trick on you; that is, these scientists dismiss it as just a glitch in the matrix. A few people are just terrified when it happens, but others feel euphoric about it. On average, most people just find it to be a perplexing sensation, neither pleasant nor threatening. Since déjà vu occurs in individuals with and without a medical condition, there is much speculation as to how and why it happens. Several psychoanalysts attribute deja vu to simple fantasy or wish fulfillment, while some psychiatrists ascribe it to a mismatching in the brain that causes it to mistake the present for the past. Many parapsychologists believe it is related to a past-life experience. Obviously, there is more investigation and researches to be done. So, does this article seem very familiar to you? 48. Which of the following CAN'T be described as a déjà vu experience based on this passage? (A) You keep buying similar style of clothing and you don't know why. (B) You feel you've been to a place when actually it's your first time there. (C) Someone looks familiar to you though you have never seen him before. (D) You just met a new friend whom you think you must have met somewhere. 49. Based on the article, which description about déjà vu is WRONG? (A) It actually is not as harmful to our mental health as we think. (B) Some people who have experienced it may feel a sense of happiness. (C) The word"déjà vu" originates from France, meaning"already seen." (D) Those who never experience it may not be mentally healthier than those who do.

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