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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B、C如何判斷?我沒有辦法把這兩個選項跟文章串起來,看不出他們有什麼關聯😭

女大考三題型 Unit 8 The Risks of Bio-terrorism In 2001 a number of US government employees and citizens died, after opening 1 letters deliberately contaminated with a deadly disease. 2 The government has responded to the threat by introducing a "Bio-Watch" system, which uses special equipment to detect unusual organisms in the atmosphere. Nevertheless, it can provide an early warning system for major towns and cities, allowing medicine to be rushed to an area under attack. 3 However, the US government is much more worried about the psychological impact, rather than the actual death toll, of a bio-terrorist attack. Any disease effectively released as a bio-weapon in a highly populated zone could cause general panic. 4 As a result of the continuing bio-terror threat, the US government is trying to make its citizens more confident that it can combat this menace. By doing so, it hopes that there will be less widespread panic. Therefore, if a major bio-attack occurs, people can take immediate action to minimize the damage. (A) This was probably the work of a mad scientist, but it signaled to all Americans that bio-terrorism was a clear and present danger. (B) This might freeze normal economic activities in the world's biggest economy center, and thus cause chaos in the global financial system. (C/Infected people can then be treated, and most will survive. DUnfortunately, this technology cannot filter the mail or prevent terrorists releasing diseases in enclosed places. 1. 2. y 3. C 4.

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英文 國中

幫我解答全部題目答案,因為我全部都不會

V 31 3 @Z/9 op www 1/9 ELOZOF 11 mp 1 What day 49 421-1 What time at 007 114 115 there are 17 ANDA 3x6 m ²²m 18 19 10210118 84 237 英語科 第2 次複習考 第2單元 8114~6 ·單題,請依文意選出一個正確或最佳的答案。 (每週3分,共453) (D) 1. What day does the boy have science class? A) On Wednesday. On Thursday, (C) On Tuesday. (D) On Friday. (A) hurry () 3 lan: Do you have the Amy: It's ten to ten, A second (B) date (C) minute Di time () 4 When Nancy studied in the USA, she lived house two American girls. A in; of (Cof, with () 5 On Chirldren's day, tickets to the zoo is (A) free (B) famous stays (A) somewhere () 2 My parents will come home late today, so they ask me to the dog after school, (1) go (C) walk ? (B) at; with (D) in; with (A) doesn't have (C) has () 13 Listen! A baby (A) cry (C) is crying () 14 I have to get up early, (A) and () 15 Ruby Sun Let's go check. (D) run (D) strong (C) quiet () 6 The man went to the hospital right after a nose. (B) kiss (A) blow () 7. Lily likes to listen to (C) cry when she is sad. (C) music (A) card (B) movie (D) spell & You are all wet. Go take a bath and make the water as hot as you can or you will catch a cold. (A) fight (B) bear (D) put (C) look () 9. Hang up the phone, please. David won't get lost. He just to cool off. (B) cries (D) cried a Sat to his (D) band (B) here (D) now (C) later ( ) 10 Did you see my black dress? I put it (A) between (B) on (D) over (C) at () 11. Fans up to see their favorite singer in front of the department store. (A) meet (C) hide (D) shake (B) line any cloud in the sky. It will be a lovely day. () 12 There (B) isn't (D) don't have 11 AT A MAR 304 the bed. I will miss the school bus. (C) when (B) or (D) until the dishes now, but she has to take out the trash later. (A) does (B) do (C) is doing (D) did 二、題組:請依所附的短文或圖表,選出一個最適當的答案。 (16~20題每題2分,1~5題每題3分,共55分) (16~20) Zoe: Hi, that's a cool bag. Alice: Thanks. Are you a fan of Red Bear? Zoe: Yes, 16 my favorite band. By the way, my name is Zoe. Nice to meet you. M B23 M Alice: Nice to meet you, too. I am Alice. A-L-J-C-E Zoe: I didn't see you before. Are you new here? Alice: Yes, it's 17 first day at school. Zoe: 18 are you from? Alice: I am from France, like my father. Zoe: Cool, Oh, the bell 19 19 What class are you in? Alice: I am in Class 801 Zoe: Me, too. We are classmates. There 20 a big tree in front of our classroom. Let me show you around. () 16 (A) there is (C) it is ( ) 17 (Wa (C) my ) 18 A) When (C) Who (19 (A ring (C) rings () 20 N have (C) are (21-22) (1) it has (D he is (D) me (1) Where (C) 《背面有試題 2-1》 (Di What (B) is ringing Alaska Boat Trip Guide This guide will help you know more about animals in or near the sea. You can see it during your trip. () 22 Which is true? (D) rang (B) bas (Dis Puffins live on the sea, and they are good at swimming. They have black, white and grey body. Their beaks are black and orange. They look cute, so they are very popular. In May, they come here to build. their nests. You can see them flying over the sea with some fish in their beaks. www. Killer whales are black and white They are not whales. In fact, they are in the dolphin family. We usually see them swim in a group and we call it pod. A good time to see those animals is from June to September. guide thi whale dolphin beak nest () 21. Which picture shows pod? (A) 2 (B) (DI (A) Puffins have black and white beaks. (B) The best time to see killer whales is in early spring. (C) Both animals can live both on land and in the sea. (D) Both animals are black and white.

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英文 國中

請幫我對答案 謝謝❗️

第19章 其他重要句型文法 *0. 2 you relax. (A) 3 up, Kim. you are. 選擇題 1. I just found out yesterday (I weigh 80 kilos) I've gained two kilos in a month. (A) that (B) which 四 gain 增加 (C) what (D if smoking helps you relax might be true, but there are some better ways to help 四 relax 放輕鬆 (A) It (B) Whether (C) That (D) X up early, or you will miss your first class. (A) Getting (B) Get (C) To get (D) Gets +(B) 4 there any fruit left in the refrigerator? (A) Is (B) Are (C) Have D) Will (B) @ I've heard some people have gotten cancer from smoking. 四 cancer 癌症 • (A) of (B) that (C) about (D) to *(13) 6. (A) Not to stand (B) Don't stand (C) Standing D Doesn't stand *(0) 7. Please the door. It's cold outside, and the wind is so strong. (A) do not open (B) not open (C) don't open (D) doesn't open *(0) 8. Kim: It there any pen-of mine on your desk? Ben: Yes, is one. Here (A) it (B) this C) that (D) there *0) 9. There only some water in the bottle. It's not enough for every one of us. (A) have (B) has (C) is (D) are (s) 10. There are millions of people the exciting game at a time. (A) watch B) to watch (C) watched D) watching ( 11 is said that Peter's father died two weeks ago. (A) It KB) This (C) That *(B) 12 It is a sad thing, (A) to Mr. Brown has been dead for two years (B) that Mr. Brown didn't live long enough to see his dreams come true (C) of me to hear the bad news (D) of Tom has made up his mind to leave here on time when you have a date with friends. (C) Do (D) Must (A) Will be (B) Always be (U) 14. It's convenient everyone can use the computer to do all the work. (D) X (C) that (A) for (B) to tomorrow or not. (B) 15. I am not sure whether Tom (C) came (D) coming (A) comes (B) will come b) They () 13

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