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化学 高校生

CODの測定の問題です。解き方を教えて欲しいですm(_ _)m 答え (1)①C6H12O6+6O2→6CO2+                    6H2O     ②57.6mg    (2)4.80mg

(オ) 単体の硫黄を燃やすと, やや実験 SDGs 4135 CODの測定 化学的酸素要求量 (COD) とは、水中に存在する被酸化性物質(主 として有機物や Fe2+, NO2など) を一定の条件で酸化分解するときに消費される酸 化剤の質量を, それに相当する酸素の質量で表したもので, 水質汚染の状態を知る 1 一つの重要な指標とされている。 CODの単位は,試料水1Lあたりの酸素消費量(mg) で表される。 分子量: O2=32.0, C6H12O6=180 (1)54.0mg/Lのグルコース C6H12O6の水溶液を試料水とする。 ① グルコースが完全に酸化分解されたとして, その化学反応式を示せ。 ② COD の理論値を計算で求めよ。 (2)ある河川で採取した試料水 200mLに希硫酸を加えて酸性とした。 ここへ,一定 過剰量の過マンガン酸カリウムを加えて30分間煮沸すると,試料水中の被酸化性 物質は酸化され, 0.00500mol/L過マンガン酸カリウム水溶液が4.85mL消費された。 また,200mLの精製水についても同じ方法で試験(空試験という)したところ, 0.05 mLが消費された。以上のことから、この試料水のCODの実測値を計算せよ。 日本女子大改)

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英語 高校生

この英語長文において、印刷技術の発達に必要な技術はどのようなものであるか50~200字で答えてください

木版画 鋳造 第3問 以下の文は、 S. Strandh の “Machines, an illustrated history" からの抜粋で ある。 次の文を読んで、設問に解答せよ。 (ア) The tools of precision mechanics were, without doubt, the technical pre conditions for making wood cuts and for the development of printing. The oldest dated wood engraving is from 1418. It shows fine lines throughout 細部 and a richness of detal, which imply that the tools used, the knives, burins, and so on, must have been eminently suitable At this time, it was only the precision mechanics of clock making which could achieve the technique required for such tools. 精密機械技術 (イ) A (woodcut was produced by transferring a drawing, reversed from left to right, onto a carefully surface-ground "block" of wood, after which the surface wood on either side of each line in the drawing was cut away with a burin of forged steel. The remaining wood on all 'surfaces which were to be white in the drawing were then cut away with gravers and gouges, so that the lines of the drawing became raised. They were then inked and pressed against paper. これは 理由では ないから、 (~のときに、何 が原因か は不明) The woodcut method spread rapidly in the late Middle Ages when pictures were rarity. At first, skilful craftsmen made the woodcuts, but before long, eminent artists were themselves cutting their own drawings in wood. One of the first was the German Albrecht Duerer (1479-1528) who, in 1498, published the famous pictorial series of the Revelation of St. John. Graphics had become an independent art form-based on the progress of precision 酒の mechanics! 可動式の The 1440s saw the first book printed with movable die-cast type. (The letter press printing method used by Johann Gutenberg (1399?-1468) was basically the same as the one used for printing woodcuts, but Gutenberg used cast, movable type instead of cut blocks. The production of dies for the type was made possible by the tools of precision mechanics, too. It does not detract from Gutenberg's contribution that printing with movable type has been practised in the Far East, or more specifically Korea, two thousand years prior to this. Several of the techniques described here, which developed so quickly during the technical revolution of the Renaissance, had had predecessors in other parts of the world. ' 金楼 にねじ を刻む 道具 ~をなら K あったもの

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