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英語 高校生

共通テストのリーディングの問題で時系列的な問題があるのですが、何回やっても正解できません、 誰か教えて欲しいです。

B You found the following message on a personal blog written by an exchange student at your school. Save Our Park! Wednesday, April 21, 2021 Vera Sherman First, thank you for visiting my blog. Today I'm writing about something very close to my heart. I hope everyone in town has had a chance to spend some time at Kaneko Park. It is a lovely place, and it's easy to walk to from our school. As it is springtime, the park is currently full of blooming trees, singing birds, and people enjoying the outdoors. Some creative students even built little squirrel houses for the animals to live in. Unfortunately, however, we need to do more to help clean up our wonderful local park. One month ago, I was taking pictures of the flowers near the pond. When I looked at the pictures at home, I noticed some garbage in the background. I spoke to Mr. Tanaka, the city official who is in charge of the park. He told me that sometimes students eat fast food and leave packaging on the ground. He said that in the past he had asked students to clean up after themselves but very few students had actually done as he asked. Because students were a big part of the problem, I felt I should take some responsibility in trying to sort out this problem. I put up flyers explaining the situation and asking for students to help after school. A small group came out, but we were not well prepared. We didn't have enough trash bags, and we did not have a clear plan for cleaning up. I went back to Mr. Tanaka, and he promised me that next time we went to the park, the city would provide trash bags and maps of locations to clean. Now we are ready to make a difference. Maybe it doesn't seem fun to spend your time picking up trash, but please consider helping. We will be meeting outside the front gate of the park at 10 a.m. this Saturday. Please try to arrive by 10 a.m. as we will be starting the litter pick straight away. Let's all help clean up our beautiful park!

解決済み 回答数: 2
化学 高校生

化学 有効数字について (4)と(5)の答えが有効数字2桁となるのは何故でしょうか? 問題文の数字は有効数字3桁まで書いてあるので、答えも3桁にすると思ったのですが...

応用例題 33 電解槽の並列連結 電解槽Aには硫酸銅(ⅡI)水溶液を,電解槽Bには硝酸 銀水溶液を入れた。 電解槽Aと電解槽Bを図のように並列 につないで白金電極を使って電気分解を行った。 電流計の読みが 0.400Aの一定値になるように調節しな がら 64分20秒間電流を通じたところ, 電解槽Aの陽極 で発生した気体は, 標準状態で67.2mL であった。 Ag = 108, ファラデー定数 = 9.65×10C/mol (1) 流れた全電気量は何Cか。 (2) 電解槽Aの陽極での反応を, e-を含むイオン反応式で 表せ。 (3) 電解槽Aに流れた電気量は何Cか。 (4) 電解槽Bに流れた電気量は何Cか。 (5) 電解槽Bの陰極には何が何g生じたか。 応例 33 脂針 電解槽A [陽極] 2H2O O2 +4H + 4e [陰極] Cu + 2e → Cu 電解槽B [陽極〕 2H2O→O2 + 4H + 4e [陰極] Ag+ +e 0.400AX (64×60+20)s = 1.544×10°C≒1.54×10°C 圏 [Pt Pt 硫酸銅(Ⅱ)水溶液 Cu 5 04 67.2mL 22.4×10mL/mol B Ag (4) 電解槽を並列につないだ場合,回路全体を流れた電気量は、各電解槽に流れた電 気量の総和である。 谷 (1) 電気量 〔C〕=電流(A)×時間〔s] より, Pt Pt 硝酸銀水溶液 AgNO3 (2) 2H2O → O2 + 4H+ + 4e (3) (2)より、電解槽Aの陽極では, e 4mol が流れると, O21molが発生することが わかる。 Oz が標準状態で 67.2mL, すなわち -=3.00×10-3 mol 発生したので, 流れた電気量は, 9.65×10C/mol×3.00×10-mol×4=1.158×10°C≒1.16×10°C 答 (4) 電解槽Bに流れた電気量は, 回路全体を流れた電気量から電解槽Aを流れた電気 量を引いたものに等しい。 したがって, 1.544×10°C -1.158×10°C=386C≒3.9×10°C 圏 (1) より (3) より (5) 電解槽Bの陰極の反応は,Ag+ + e. Ag e1mol により Ag1mol が析出する。 電解槽Bに流れた電子は 386 C -=4.00×10-3mol であるから, 9.65×10 C/mol 108g/mol×4.00×10-mol = 0.432g = 0.43g の 銀 Ag が生じる。 答 10

解決済み 回答数: 1