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化学 大学生・専門学校生・社会人

吸光度法の計算問題なのですが、どのように計算していったら良いのか全く分かりません。教えていただけると嬉しいです…!よろしくお願いします🙇‍♀️

3 弱酸の酸解離定数Kaを吸光度法で求める方法に関する文章の 濃度 Cmol/Lの弱酸水溶液中に存在する弱酸分子(HA), 弱酸イオン (A) および水素イオン (H+) に適当な語句を入れよ。 の濃度を、 それぞれ, [HA][A] および [H+] とすると, CHA+[A] Ka= が成り立つから, pK を知るためには, [HA] [A-] (3) が成り立つときのpHがわかっていればよいことになる。 いま、この溶液のある波長における吸光 度4を光路長 lcmのセルを用いて測定するものとする。 この波長での光の吸収が溶液中の [HA] および [A-] のみに起因するものとし、 [HA] および [A] のこの波長におけるモル吸光係数をそれ ぞれ 81 および e2 とすると、 溶液中の[HA]に基づく吸光度 4 [HA] および溶液中の [A-] に基づく吸光 度A [A-]は, それぞれ, A [HA] A [A-] 表される。 また, = = Є1 = log Ka=pH- A=A[HA] + A [A-] であるから,式 (3) のもとでは,Aは1, 2, lおよびCを用いて, (1) (2) (4) (5) (6) A = 129 (7) で表される。 一方, pHが極めて低いとき ( [HA] >> [A-]) の 4 を A1, pHが極めて高いとき ( [HA] << [A-]) の 4 を A2 とすると, (8) (9) €2= が成り立ち, 式 (8) 式 (9) を式 (7) に代入することによって, 式 (3) は, A = (10) と書き換えられる。 すなわち, 実験では、濃度が等しいが pH が異なる酢酸溶液をいくつか調製 し、同一条件でそれぞれの吸光度を測定して, pH と吸光度の関係をプロットするし, 式 (10) の関係が成り立つときのpHの値を求めてそれをpKaとすればよいことになる。

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英語 高校生

これの100字要約日本語でしていただけませんか?

5 19 A concerted drive to reduce obesity in one Australian town resulted in a whole generation of slimmer, faster, and healthier children, researchers reported yesterday. They said that the program, a simple mixture of persuasion and (A)incentives, was astonishingly successful. It led to 2,000 children gaining less weight, watching far less television, taze (and playing more sports. The "Be Active, Eat Well" project, conducted by Deakin University in the small town of Colac, 150 km southwest of Melbourne, ended with Colac's children weighing an average of one kilogram less than the norm for Australian children of their age. Their waistlines were an ウェスト average of cm smaller - 2 cm for boys and 4 cm for girls. Professor Boyd Swinburn from Deakin University in Melbourne said yesterday that the Colac experiment had proved to be "astonishingly successful." It was the first such program in the world to report significant reductions in waistline and weight. Professor Swinburn said: "Most people would think individual weight loss of one kilogram is not much, but here we're talking about shifting the weight of a couple of thousand kids, and 15 that's actually quite (B) phenomenal. In fact, across a population, that is absolutely huge." The experiment began three years ago when the university researchers descended on Colac's population of about 10,000 people, urging parents, teachers, doctors, and local fast-food outlets to support changes for all children aged between 4 and 12. The program included opening up more after-school activity centers for children and introducing 20 brightly colored lunch packs that contained a pitta salad wrap*¹ and fruit tub2. Parents were encouraged to (c) monitor strictly the amount of time their children watched television or walk or cycle to They were asked to encourage their children spent on computers. (3) school rather than drive them. While the researchers had hoped to cut television viewing by 10 percent, the final results 25 reported children's television viewing had dropped by 21 percent and soft drink consumption by 70 percent. There was an increase of almost 70 percent in the number of children participating in after-school sports. 10 7. ★★★ 参照チェックノート p.38 414 words 56 早稲田大学 Even the town's fish and chip shop owner switched from using animal fats to sunflower oil. He reduced the saturated fats3 in chips from 49 percent to 9.1 percent. The other fast-food outlets 30 also switched from animal fats, leading to a cut in saturated fats consumed in the town of 55 kg a week. Adults then began to follow their children's example, and the local self-defense academy went from 16 members to 75. pitta satu 1 (A (

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