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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

想請問43題為什麼是(D)?看了詳解還是不懂希望大神幫忙解題~(這是106學測題!)(看題目的時候會一直圈有點亂請見諒(^^;;)

41-44題為題組 Dognition will help you learn more about your dog's cognitive traits. It offers an online test Is your dog an Einstein or a Charmer? For US $60, a recently-founded company called telling you about the brain behind the bark. Dognition's test measures a dog's intellect in several aspects-from empathy to memory to reasoning skills/ But don't expect it to measure your pet's IQ.) Dr. Hare, one of the venture's co- founders, says a dog's intelligence can't be described with a single number. Just as humans have a wide range of intelligences, so do dogs. The question is what type your dog relies on more. After you plunk your money down, Dognition's website will take you through a questionnaire about your dog: For example, how excited does your dog get around other dogs, or children? Do fireworks scare your pup? Then, Dognition guides you through tests that are as fun as playing fetch or hide-and-seek. At the end, you get a report of your dog's cognitive profile. Your dog could fall into one of nine categories: Ace, Stargazer, Maverick, Charmer, Socialite, Protodog, Einstein, Expert, or Renaissance Dog. That can give you something to brag about on Dognition's Facebook page. It also can shed new light on why dogs do the things they do. For example, a Charmer is a dog that trusts you so much that it would prefer to solve problems using information you give it rather than information it can get with its own eyes. Dognition helps people understand their dogs in ways that they have never been able to do. This new understanding can enrich the relationship between dogs and their owners. B 41 What is the third paragraph mainly about? (A) The theory behind the questionnaire used in the Dognition test. (B) The procedure for evaluating a dog's intellect on Dognition. D The products one can get by paying a fee to Dognition. (D) The characteristics of the activities Dognition offers. 又 42. According to the passage, which of the following statements is true? (A) Different dogs display strengths in different intelligences. BA dog's cognitive profile is composed of nine cognitive skills. The purpose of Dognition's testing is to control a dog's behavior. (D) A dog's intelligence can be ranked based on the score of a Dognition's test. K 43. Which of the following is closest in meaning to the word "venture" in the second paragraph (B) Risky attempt. (D) New business. (A) Creative measurement. 53% (C) Non-profit organization. 569 29 xyzcd.

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英文 高中

想請問第24.題,為什麼rather than不用接動名詞replacing,謝謝!

b ✓ D 第21.至25.題為題組 power reality, autonomous vehicles and networked robots. Besides, it will also promise- We are now on the threshold of a new era of 5G networks. 5G will 自动的 procedures, safer transportation and more immersive gaming experiences. Faster speeds, fastes the three changes 5G is all about. 21. connections and faster access to the cloud are Up to 100 times faster than 4G, 5G will provide a speedier connection to the phone. Plus, service and allow more devices to connect to the netw 22. extra bandwidth will ensure a more at the same time. However, 5G's super-high-frequency airwaves can't travel through walls rooftops, and they become weaker over long distances. As a result, numerous miniature cell to inside and outside the buildings for better efficiency. Also, while 5G might pre must be 23. a speed boost in buildings and crowded areas, 4G will still be in use to cover wider areas i 24. replace 4G directly. meantime. In other words, 5G will work with 4G at first In spite of its limits, the 5G network can function as á cloud server and help self-drivir 25. of an eye. It to process all the needed information to make critical decisions in the 22. (A) innocent 23. (A) installed 24. (A) other than smart believed that 5G can help improve telemedicine and robotic surgeries and thus provide better services. Hopefully, 5G technology can bring human civilization a great leap forward. 21. (A) scarcely 几乎不 I Scarrely thin leisurely (B) reliable (B) related (B) in order to (B) clap 25. (A) drip 第26.至30.題為題組 cities, (C) appropriately (C) pessimistic (C) violated (rather than (C) brick new surgic (D) essentially (D) criminal (D) threatened Dwith a view (D) blink Eating as many fruits and vegetables as you can is thought to be for good health. B the fruits or veggies on your shopping list are not in season or will be eaten much later in Frozen veggies would be a good alternative. But with many myths 26. around today d frozen foods, people often perceive frozen veggies as less healthy. In fact, most researc- that frozen vegetables are just as nutritious, if not more nutritious as their fresh counterpa

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