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化学 高校生

問題42の解き方を教えてください 学校でやりました。 問題42の下は友達が教えてくれた解き方です。

教良151 参考 炭酸ナトリウムの二段階中和 炭酸ナトリウム Na2CO』 は弱酸の塩で,その水溶液は塩基性を示し, 塩酸 HCIを加 えると, 炭酸水素ナトリウム NaHCO」 を経る次の2段階の中和反応が起こる。 Na2CO3 + HCI NaCl + NaHCO3 (a) NaHCO3 + HCI → NaCl + H2O + CO2 (b) 式(a) の中和点 (第1中和点) は, フェノールフタレ インの変色(赤色→無色) で、 また,式 (b)の中和点(第 2 中和点)はメチルオレンジの変色 (黄色→赤色) で判 定できる。 物質量に注目すると, Na2CO3 が α [mol] のとき, 式 (a)で反応した HCI はα [mol], 生成した NaHCO3 も[mol] となり, 式 (b) で反応する HCI もα [mol] となる。 例えば, 0.1 mol/L炭酸ナトリウム水溶液10mL を0.1mol/L塩酸で中和滴定した場合, 式 (a) と式 (b) での塩酸の滴下量はともに10mL で等しくなる。 a mal. Na Na Co amel amdl Na2CO3+HCl→NaCl + NaHCO3 ↓ cl HiCOS 中性 ができるけど Amal 水の中でしかできないし 不安定だから すぐに水と二酸化炭素になった Naz CO」 は NaHCO」 より塩基性が強い ため, 式(a)の反応後 式(b)が始まる Na2CO3水溶液のpHは11.3 OH amol amol and Aniol NaHCO3 + HCl→NaCl +CO2+H20 ✓ し cl 中程 Nà HCO 酸性 cs CamScanner でスキャン NaHCO、水溶液のpHは8.5 [第1中和点 NaHCO, メチルオレンジ 変色 図炭酸ナトリウム水溶液 の滴定曲線 0.1 mol/L 炭酸ナト リウム水溶液10mL を 0.1mol/L 塩酸で中和滴定した場合。 NaHCO, Đ Nâ4 CO H20 H ・第2中和点 - -H2O+CO2 塩基性 ? 塩基性がまだある Na2CO」は2価だけど 1価しか使わない。 AS Nacl 強塩基 弱酸 H2CO3 → H2O+CO2.. 中性弱酸

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数学 高校生

(2)の線を引いたところが分かりません!求め方を解説お願いします🙇🏻‍♀️

第5問 (選択問題) (配点 20 正射影されたベクトルについて考える。 (1) d = 0, 万 0 とする。 右の図において、夢をのへの正射影ベクトル という。 すなわち万の始点、終点をそれぞれ A, B とし, A, B から に平行な直線に垂線 AA', BB' を引くとき、 AB' が の への正射影ベクトルアである。 ことのなす角が0° < 0 90° を満たすときとは向きが同じである から,' =ka (kは正の実数)と表される。 そこで, kを次の方針1または方針2によって求めてみよう。 がとらのなす角であるから ME 方針 1 の大きさは万の大きさと0を用いてア と表される。 からkを求める。 B Ax 方針 2 条件より, このことからんを求める。 イ A' が成り立つ。これらのこと と d が垂直であるから, ウ との内積は0である。 (数学ⅡⅠI・数学B 第5問は次ページに続く。) 方針 1,方針2より,k= の解答群 Obsin 0 6 sin イ の解答群 sin0 = sin0 = a・b a.b |ab| の解答群 a の解答群 a2 a・b I ① cose 6 cos 0 4 であるとわかる。 ① cost= ④④ cost= ① B' 62 a.b ab a・b a.b ab 4² ②6tane 6 tan 0 ⑤ 1? (02Q2 2b+b a・1 tan 0 = tan 0 = ab a.b a・b ab (3 7-6 a.b b Z (数学ⅡⅠ・数学B 第5問は次ページに続く 広 =k (2)

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英語 中学生

英検対策の問題です。 中1なのですか分からないとこばっかりで…。 解説も出来れば、出来ればでいいので お願いします🙇‍♀️⤵️

13 (1) から (15) まで ( 1つ選び、その番号のマークをぬりつぶしなさい。 (2) (1) A: Mike, have you called Jill to tell her about our meeting tomorrow? B: No, not ( 1 yet ―次試験 筆記 ). I'll call her after lunch. 2 over 3 always Brian is going to visit the (> ) with his class next week. He wants to see many kinds of fish there. 1 college 4 garage 大学 EL (3) A: These are delicious tomatoes. B: Thank you. We ( 1 grew に入れるのに最も適切なものを 1,2,3,4の中から 2 aquarium 3 stadium *17 (7) A: It's so hot! 2 thought 2 special (6) Helen and Yumiko ( they're good friends. 1 put (4) Jeff went fishing on Sunday. He caught nine fish. One was very big, but the () were small. 1 another 2 ones 3 others 4 sometimes (5) A: I heard that you're going to Rome next week. B: That's not ( ). I'm going to Paris. 1 true 2 thought ) them in our garden. 3 fought 4 knew 4 all 3 met 3 common 4 main 3) in the tennis club at school. Now 4 found B: Here, use this (2). It will cool you down. 2 fan 3 hill 71% 1 line 4 head 頭 75 78 (8) People think I can speak French because my mother is from France. But (A ) fact, I can only speak English. 1 by 2 on f 3 for 4 in (9) The rock group was very popular, so the concert hall was 3) of people. ( 1 thick 2 full 3 deep 4 high (10) Lisa and her family didn't go ( planning to go on a trip this year. 1 away 2 at B: OK. 1 pass (11) A: I told my mother that I would be home by 7:00. I don't ) my promise, so I have to go now. want to ( 2 se 4 lend 2 color 3 through 4 behind (12) Jim bought a new house, so he had to move his things. All his friends were on vacation, so they couldn't give him a (/). 1 part ) last summer, so they're 3 break (13) A: Excuse me. Could you tell me ( map? 2 won't 3 front (14) A: Jack is a police officer, (3 B: No, he's a doctor. 1 isn't 2 to teach B: Sure. There's a bookstore on the fifth floor. 1 which 2 why 3 what 4) I can buy a world ) he? 4 hand 3 doesn't 3 teach 4 where 4 can't (15) I can't ride a bike, but my brother can. I asked him (3) me. 1 teaches 4 taught 19年度第1回 記

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英語 高校生

1枚目の本文に対する2枚目の問題の答えを3-イか3-ロで迷っているのですが、どちらが正解かわかりません。どなたか理由もあわせて教えてもらいたいです。 よろしくお願いします!

Omoiyari is said to be a key concept of the Japanese mentality. (Its primary meaning is the ability to imagine other people's feelings. Japanese people's good manners have often (2) been associated with it and reported in news articles. For example, Japanese soccer supporters cleaned up the stadium after the matches at the World Cup, actions that were praised by the foreign media. Some experts say the supporters' behavior is related to education in Japan, where children clean their classrooms every day. Another example was seen during the frequent natural disasters. Even in such situations, many people still kept calm and patiently waited in lines for emergency supplies. JANET [ 3-1 ] According to a survey by an organization to promote good manners in Tokyo, less than 30 percent of Tokyo residents think people in Tokyo have good manners. [ 3-□ ] For example, Tokyo residents notice bad manners on the train. (4)Some young people sit in priority seats and do not give sit (5). V₂ 1 up their seats to the elderly, and others put on makeup. [ 3-> ] In an effort to get the passengers to 52 act more (5), railway companies display posters, saying things such as, "Please line up and c wait your turn" or "Please switch your phone to silent mode while ( 6-a) the train." 5 [ 3-= ] Omoiyari is often seen in school mottoes and emphasized in moral education at school. Some of the values that students are ( 6-b) include respecting the elderly, helping those with disabilities, and keeping promises. Students also take turns (6-c) in charge of cleaning the classroom, serving lunch, taking care of plants and animals. In addition, volunteer clubs collect money for charitable organizations and members visit elderly people in nursing homes. In moral education class, students read stories and discuss the topics in them. The teacher facilitates the discussion and the students draw their own conclusions. (Nakaya, et al., Discuss the Changing World, Seibido)

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数学 高校生

114の問題では、(表、裏)、(裏、表)とするのに115の問題では(1、2)、(2、1)としないのはなぜですか。115の問題には(左<右)としているのはダブりを防ぐためと書いてありますが、表と裏には大小関係はないですが同時に出すのであれば(表、裏)、(裏、表)もダブりになる... 続きを読む

基礎問 188 第7章 確 率 第 7 章 確率 114 同様な確からしさ(I) 2枚のコインを同時に投げるとき、次の問いに答えよ. 6 (1) 2枚とも表になる確率を求めよ. (2) 1枚が表で,1枚が裏になる確率を求めよ. O JANNE 2枚のコインを投げるとき 2枚とも表, 2枚とも裏,1枚が表で 1枚は裏, の3通りの場合があります。 3 したがって, 「だから,表が2枚でる確率は - 」 というのはウソ!! 確率を考 えるとき,「全体がN通りで,起こる場合の数がn通りだからその確率をN」 としたければ, N 通りの1つ1つの場合が同様に確からしくないといけません。 たとえば, 飛行機は「落ちる場合」 と 「落ちない場合」 の2つがあるから, 「飛行機の落ちる確率はである」とは,どう考えてもおかしいでしょう? 2 |精講 解答 1枚のコインには表と裏の2通りがあるので、 2枚のコインは (表,表), (表裏) (裏、表) (裏,裏) の4つの場合があり, それらは同様に確からしい. (1) 2枚とも表になる確率は (2)1枚が表,1枚が裏になる確率は 12/2=12/2 == 4 ポイント 演習問題 114 全体がN通りあり, その1つ1つが同様に確からしい 確率=起こる場合の数 N 3枚のコインを同時に投げたとき、 同じ面だけがでる確率を求めよ.

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英語 中学生

⑦に入る2語を答える問題です! 答えがfour hoursなのですが、なぜそうなるのですか?私はeight hoursだと思いました!!

10 15 20 5 6 次の英文は Olango という森の中にあるいくつかの村に住む動物たちの対話です。 これを読んで、あとの問いに えなさい。 Ay 40 was ' Kabbu is head of the Post Office of Olango, a forest. Many kinds of animals live there. Kabbu and his tea carry letters all over Olango and to other forests. Kabbu's Post Office is very popular among all animals there. Ullu: Why are you so sad? Kabbu: *Probably we'll have to lose my job. Have you heard of the Internet? Ullu: Have humans planned to catch us with a new kind of net? Kabbu: No, no. I hear the Internet is new *technology. All the computers can talk to each other through the Internet. We can talk with everyone around the world by a computer. Leo has the newes computer. He is always using it. He has also made many friends through the Internet and talk with them for hours. Ullu started to think about the Internet after he listened to Kabbu's long report about it. Ullu: Tell me, Kabbu, why will you have to lose your job because of the Internet? Kabbu: Leo is now sending e-mails all over Olango and to other forests. He says everyone in this village will be able to use his computer and send e-mails from his computer. Now, if everyone starts sending e-mails, ① 私たちはどうすればよいのかわかりません。 45 Ullu: Wait, wait. Now what is 'e-mail'? I haven't heard of it. Kabbu: It means *electronic mail'. It is used to send every kind of letter from one computer to other computers through the Internet. It takes only *a second and it is almost free. Ullu: I can't believe it. Kabbu: It is true. So I am very sad and worried about it now. With a sad face, Kabbu flew away. Kabbu was the oldest animal in Olango and was respected a lot by Leo Ullu decided to go and meet Leo and talk with him. At Leo's house, Leo was sitting in front of his computer. Ullu: Leo, can you give me a few minutes? I have to talk about something important. Leo: What is it? Ullu: It is about Kabbu, but I think it may be about all of us. Leo: OK, tell me about it. Ullu: But Leo, I think 50 55 1 60 Ullu told Leo about Kabbu. Leo: Well, Kabbu's *concerns will be real. We usually think high speed and *efficiency are very important, so there is little *chance for old ways. I can send a message in a second through the Internet. But Kabbu and his team need a few days to carry one. Why should I *depend on them? And the *price of their mail is much higher than the price of e-mail. Ullu: But, Leo, what will happen to Kabbu and his team? Leo: They will have to 3 The Internet will become more important in the future and e-mail will be one of the most useful things. 4 trains in the future." But now, "No one will go to see a movie." But both... Leo: You may have a lot of things to say about it, Ullu, but soon e-mail will make Kabbu's mail *useless. Kabbu and his team should start looking for other jobs *after all! For example, when a plane was invented, people said, "No one will see trains still continue to run. When a TV was invented, everyone said.

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