年級

問題的種類

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.

待回答 回答數: 0
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

待回答 回答數: 0
英文 高中

想問第四題為什麼不能選C 謝謝🙏

111. 綜合測驗:15% • pose drult qi avil or salil olgooq vasi 26 have fascinated 1. of a e part lunches daily to The dabbawalas of Mumbai, i, India, have ated many people. They are boxed-lunch delivery organization that brings around 200,000 office and factory workers. Dabbawalas provide a very useful service. Since most Mumbai residents live in areas far from their jobs, it's inconvenient for them to bring their lunches on cramped public transportation. Dabbawalas always deliver the lunches the right location. They're able to do this because of their nearly-3./ operating system. collects around Each geographical area* employs around twenty-five dabbawalas, 4. 8, and details. outer delivery of 2. and to thirty lunch boxes boxes. Dabbawalas write special numbers and characters on each container's 5., they rarely lid to indicate the neighborhood, building, deliver a lunch box to the wrong place. Without a doubt, the service performed by these dabbawalas is a true model of success. el of successivo a god m' .01 (A) It wasn't mentioned in the passage. 90.87 Ji a geographical area 註: home-making (C) home-made BID 2251 (C) 1. (A) home-make eded (B) home-maki (D) making-home SD) 2. (A) at risk (C) by chance (bai (D) on time (B) & (A) classic list! (B) all the time (solo (C)(A) each of whom A (B) flawless (B) one of which (C) each of them JESSIES anoia ( handled 101 airli(D) swift (D) they all

尚未解決 回答數: 1
1/12