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化学 高校生

油脂についてです。 (C)の解答で、私が青線でラインを引っ張った行の下にある構成脂肪酸の分子量を求める式にある、+1が何を意味しているかが、わかりません。 また、その下の「(B)より脂肪酸一分子には〜と表すことができる」のところについてですが、COOHのところに二重結合が一... 続きを読む

脂の道> 文中の(A)~(C)に最も適合するものをそれぞれ(ア)~(オ)から選べ。 H=1.0,C=12, O=16, K=39, I = 127 油脂に水酸化カリウム水溶液を加えて熱すると, 油脂はけん化されて,脂肪酸のカリ ウム塩とグリセリン (1,2,3-プロパントリオール) が生じる。 ん化価とは, 油脂 1g を完全にけん化するのに必要な水酸化カリウムの質量 (mg 単位,式量 KOH=56) の数値をいい, 油脂の分子量の目安となる。 また, ヨウ素価とは, 油脂に含まれる不飽和脂肪酸の C=C 結合にヨウ素を完全に付加させたとき, 油脂 100g に付加するヨウ素の質量(g単位)の数値をいう。 平均分子量(A)の油脂 W のけん化価は191, ヨウ素価は174である。このとき,油 脂1分子中に含まれる C=C結合の数は平均 (B) 個である。 油脂 W が一種類の不飽 和脂肪酸だけで構成されている場合,この不飽和脂肪酸の分子式は (C) である。 A: (ア) 794 (イ) 800 (ウ) 878 (エ)902 (オ) 960 B: (ア) 2 (ウ) 6 (イ)3 C: (ア) C16H28O2 (1) C16H30O2 (エ) 9 (オ)12 (ウ) C18H30O2 (1) C18H32O2 (オ) C18H34O 2 [18 早稲田大〕

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英語 中学生

これの答えがないためだれか答えを教えてください‼️‼️よろしくお願いします🙇🏻‍♀️‪💧

[B] The Threat of Tourism As air travel gets cheaper, more and more people are visiting famous sites around the world. Although this increase in tourism brings economic benefits to the areas around these sites, tourists also cause unexpected problems. In particular, some famous works of art are being affected. This is because people's breath increases carbon dioxide and humidity levels. Gradually, these levels damage, old paintings and other works of art. One famous site facing this problem is the Sistine Chapel in the Vatican in Rome. The 500-year-old paintings, especially the famous ceiling by Michelangelo, are so popular that as many as 2,000 people may be viewing them at a time. In 1994, after noticing that the visitors' breath was damaging the paintings, the Vatican purchased an expensive air-conditioning system to protect them. However, the crowds continued to increase, so in 2014, the Vatican decided to limit the number of visitors to about 6 million a year. Another site that faces a similar problem is the Mogao Caves in Dunhuang, China. These caves are full of beautiful Buddhist paintings and sculptures that attract thousands of visitors every year. Many of the artworks are very old and, as with the Sistine Chapel, the carbon dioxide in the breath of visitors is gradually damaging them. Originally, 40 of the 400 caves were open to visitors, but this number was reduced by half in 2014. In addition, the number of visitors allowed into the caves has been greatly reduced. A different solution is being tried in the Ajanta Caves in Maharashtra, India. The caves also have many ancient Buddhist paintings in them, and these too are being damaged. In order to protect the paintings, visitors are quickly rushed through the caves. However, many visitors complained about the short time, saying they could not look at the paintings properly, so the local government built a visitors' center with exact copies of the caves. Visitors are allowed to study these copies for as long as they like. The local government hopes this will provide a good balance between protecting the paintings and giving tourists a good experience. (30) As the number of tourists increases, 1 unexpected economic problems occur among people living around famous sites. 2 the carbon dioxide and humidity in their breath harm the things they go to see. 3 air pollution caused by the carbon dioxide from airplanes increases. 4 people have trouble breathing because of the high levels of humidity. (31) In 1994, the Vatican 1 allowed only 2,000 tourists to look at its paintings by Michelangelo. 2 invited 6 million visitors to see its 500-year-old wall paintings on one day. 3 installed an air-conditioning system in order to make visitors more comfortable. 4 tried to reduce damage to its paintings by buying an air- conditioning system. (32) What is one thing that has been done to protect the Buddhist artworks in Dunhuang? 1 More of the Mogao Caves have been closed to visitors. 2016年度第2回 新試験 2 Visitors are being asked to avoid breathing too close to the paintings. 3 Some of the visitors are being taught new ways to preserve paintings. 4 The number of visitors has been reduced from 400 to 40 a day. (33) Why were some visitors to the Ajanta Caves unhappy? 1 The majority of the paintings have turned out to be copies. 2 There were not as many Buddhist paintings as they had expected to see. 3 They did not have enough time to look at the paintings inside the caves. 4 The long lines at the visitors' center have prevented them from seeing the paintings. 29

解決済み 回答数: 1
数学 高校生

(2)の解き方がわかりません。解説お願いします。 また、逆関数にしたくてもできない時に、置換積分をする理由を教えて下さい。

基本 例題 178 曲線x=g(y) とy軸の間の面積 次の曲線と直線で囲まれた部分の面積Sを求めよ。 (1) y=elogx, y=-1, y=2e, y 軸 0000 (2) y=-cosx (0≤x≤n), y= x=1/2 1 y=- y軸 2 p.300 基本事項 3 重要 184- 指針 まず、曲線の概形をかき, 曲線と直線や座標軸との共有点を 調べる。 (1) y=elogx をxについて解き, yで積分するとよい。 y x=g(y) d .....xについての積分で面積を求めるよりも, 計算がらくに なる。 常に g(y)≥0 C (2)(1) と同じように考えても, 高校数学の範囲ではy=-cosx を x=g(y) の形にはできない。 そこで置換積分法を利用する。 (1,2) ともに別解 のような, 長方形の面積から引く方 s=$g(y)dy 法でもよい。 (1) の別解 (長方形の面積 x=ex から引く方法) S=e2(2e+1) (1) y=elogx から x=ee JA 答 よって -1≦x≦2eで常に x>0 2e S=Seedy=[ee] =e•e-e.e-c e2. 2el S 12e e2 =2e3+e² 7-12-2 (2)y=-cosx から dy=sinxdx よって S=Sª‚xdy=S*=* 3 xsinxdx =-x x COS x 1 + 3 π cosxdx =-27 ·(-1)+ 1.1/1 π π + +0= 3 TC 2 3 2 +sinx| 2-3 3 12 -1 2e+1 2 ya y 1 1 2、 0 8 S - π 3. 3 12 → → 1223 π y=COSA 123 122 12 π -(elogx+1)dx -[e(xl0gx-x)+x] =e³-e¹- (2)の別解 (上と同じ方法) S=11x · (+1) -S 2 -cosx+ 1/2)dx x+sinx−2x] π 2 x 半の曲線と直線で囲まれた部分の面積Sを求めよ。 1 fich

解決済み 回答数: 1