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英語 高校生

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Lesson 19 , od ne mi m om a get their support. 5 He himself was through far-reaching reforms. He abolished slavery, introduced a *bureaucracv and 298628 ig piaum. ofh al nao o litmo of the 2010s, donated about 90% of his salary to charities which helped poor people. The he was often described as the world's *humblest head of state. Not all leaders are like them. Unfortunately, some leaders only care about their statis 15 When their popularity declines, they often try to shift the criticism onto others so as to maintain their power. The class system during the Edo period aimed at dividing people into classes and giving them contentment by encouraging them to look down on the lower classes. Hitler managed to win people's support by setting *Jews up as their enemies. It is quite difficult to satisfy everybody and unite a nation. Nevertheless, good leaders smo ons Tanolaom nd listen to people's voices, including critical ones, to make better policies for the welfare of 20 naw asng-1agie all the people from the perspective of national interests. So when you are qualified to vote, collect as much information as possible about candidates and political parties. It will help Coo b you judge whether they are willing to create a better society or are just trying to ake 25 advantage of their status for their own benefits. Your single vote can make a big differèIto to our future. oiauM 9oitasrf o eysW ) 363 words

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化学 高校生

この問題でフェノールフタレインが指示薬と分かる理由はなんでしょうか?

シュウ酸二水和物 H:C2O4·2H20 の結晶 0.630gを水に溶かして。100 mL にした。 基本例題 21 中和満足 シッウ酸二水和物 H.C:O4*2H.O のの結晶 0.630g を水に溶かして。100mLにした。 -のシュウ酸水溶液を。10.0mLとり,水酸化ナトリウム水溶液を。滴下したとこ る中和点までに 20.0mL を必要とした。H=1.0, C=12, O=16 とする。 »115 (1) 操作@, ⑤, ©に用いる器具の名称を記せ。 (2) 指示薬として適当なのは, メチルオレンジ.フェノールフタレインのいずれか。 (3) 水酸化ナトリウム水溶液のモル濃度を求めよ。 指針(1)溶液の調製……メスフラスコ 溶液の滴下…ビュレット (3) 中和の関係式 酸の価数×濃度×体積=D塩基の価数×濃度×体積 より求める。 解答(1) メスフラスコ (2) フェノールフタレイン 一定量の溶液の採取 ホールピペット 溶液の混合………コニカルビーカー D ホールピペット © ビュレット 0.630g 126 g/mol (3) H.C.O4·2H:0=126 より, 0.630 g は =0.00500 mol。 これを溶かして 100 mL(=0.100 L) にした溶液のモル濃度は, 0.00500 mol -=0.0500 mol/L 0.100 L NaOH水溶液のモル濃度をx [mol/L] とすると, 中和の関係式 acV=bc'V' より, 20.0 L L= 1×x [mol/L]× 10.0 HCI+ HO 2×0.0500 mol/L×- 1000 1000 OuEの物質量 HH

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