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化学 高校生

[大至急]高1の化学です。1枚目の実験結果をもとに水酸化ナトリウムの純度を出すのですが、やり方が分かりません。教えてください!

【目的】 メチルオレンジ溶液を用いて、 水酸化ナトリウムの純度を求める。 【 薬品、器具】 水酸化ナトリウム (1粒), 0.2mol/L 塩酸 (厳密な濃度は板書参照)、秤量皿、 純水、メチルオレンジ溶液、 ビュレット、 ビュレットスタンド、 ろうと、コニカルビーカー、 ビーカー、 三角フラスコ、薬さじ 【操作】※実験中に気づいたことがあれば、 適宜メモをとる。 1) コックを閉じたビュレットに、ろうとを用いてごく少量の0.2mol/L塩酸を入れ、 共洗いを二回行う。 廃液は廃液ポリビーカーに入れる。 (クラスによっては共洗い不要のこともあるので、教員の指示に従うこと。) 2) 再びビュレットのコックを閉めて、 0.2mol/L塩酸をやや多めに入れる。 ビュレットの 先端に溜まった液を洗うため、少し捨て、 目盛りを0.00mL に合わせる。 3)電子天秤、薬さじ、 秤量皿を用いて、 水酸化ナトリウム1粒の質量を素早く測り、すぐ にコニカルビーカーに入れる。 (できるだけ小さい粒を探すこと。)薬さじ、 秤量皿は2回目 の実験でも用いるので、 各班の実験台の上に置いておく。 4)3)のコニカルビーカーに水差しに入った純水を20mL程度入れ、よく振り溶かす。 (振り方注意。) 塩基性黄色 酸性=赤性 5) 4)のコニカルビーカーにメチルオレンジ溶液を3滴 ~4滴加える。 6) 塩酸の滴定開始時の目盛を表1に記入し、滴定を始める。 薄いオレンジ色になった ところを滴定の終点とする。 7) コニカルビーカーの中身を廃液ポリビーカーに入れ、 水道水でよく洗い、 純水で器具の 壁面を置換する。 8)3)から7) をもう一度繰り返す。途中、 塩酸が足りなくなった場合、 適宜、 教員に 申し出る。 【終了後】 コニカルビーカーを水洗いし、 流しの水をはったバケツの中に入れる。 ビュレット内の 塩酸の処理は教員の指示を仰ぐこと。 【観察記録 】 表1 滴定結果 (塩酸と水酸化ナトリウム (粒)) ① NaOH の質量 /g 始点 /L 0.076 1回目 2回目 今回の塩酸の mol 濃度 【 0.03. 0.03. 0:197 1 】mol/L 終点/mL 9.35 ②-③滴下量 /mL 9,32 NaOHの式量 40,00

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英語 高校生

日本語訳をお願いしたいです!!お願いします

次の英文を読んで、設問に答えなさい。 Everybody wants to eat delicious and safe food. However, exposure to different cultures reveals 2 how people's attitudes towards food safety and taste are not all innate or biological. Assumptions and practices regarding the preparation and presentation of food highlight the influence of culture on what and how people eat. For example, in one culture, some kinds of fresh ingredients might be considered edible (a), that is, without any kind of preparation like washing, peeling or heating. Yet in another culture, the same foodstuff may require some kind of preparation before it can be eaten. It is often difficult for people from the same culture to view such activities and beliefs objectively, and so witnessing the food practices of other cultures can be surprising. Sashimi is a great example of this. While sashimi may be the result of several steps of preparation from cleaning and cutting, to a particular style of presentation - heating is not one of these steps. (2)Japanese consumers take it for granted Cultures, the conventional belief may be that real and fish require some sort of cooking, such as baking or frying, (3) in order (b) them to be considered edible. In these cultures, sashimi is not thought of as raw, delicious and safe to eat, but rather as uncooked, and therefore possibly unsafe to eat, regardless of how it may taste. Fresh chicken eggs are another raw foodstuff commonly eaten in Japan — as a topping for rice, or as a dipping sauce for sukiyaki, for example but most people in the UK or the USA believe that chicken eggs require some kind of heating before they are fit for human consumption. However, the ways in which people from other cultural backgrounds eat certain foods might be considered equally unconventional by many Japanese. For example, few Japanese would eat the skin of apples or grapes. In this case, the difference involved in the preparation of the food is not the use of heat, but the removal of part of the foodstuff. People in much of the world eat apples and grapes without peeling them. A European might think, What could be more healthy and delicious than picking an apple from the tree and eating it?' But this way of thinking is not shared by a large number of Japanese. (4) It is clear that different cultures have different conventions regarding the preparation of particular foods, and different beliefs about what is considered delicious. However, there is no question that some common food preparation practices - or sometimes a lack of certain food preparation processes - are unsafe from a scientific point of view. However delicious they may be, raw meat and fish can contain the eggs of harmful parasites like tapeworms, which are often undetectable. If chicken eggs are not properly stored, and are left unconsumed for a long time, they can easily produce bacteria like salmonella. The poisoning caused by salmonella does not usually require hospitalization, but it can be very dangerous for young children and elderly people. In addition, while eating the skin of apples and grapes may be a good source of dietary fiber, one also runs the risk of consuming insecticides, the poisons that are used to protect many non-organically farmed fruits from insects. So, while there may be 'no accounting for taste' beyond culture, safety is a different issue, and (5) we should always be aware of the risks involved with culturally accepted methods of food production and consumption. 問1 下線部 (1)で,空欄 ( a )に入る最も適切な語句を, (A)~(D)から選び, 記号で答えなさい。 (A) as is clear (B) as is fresh (C) as they are (D) as unclean 問2 問3 問4 問5 下線部(2)を日本語に訳しなさい。 下線部 (3)の空欄(b)に入る語(1語) を書きなさい。 下線部(4) を日本語に訳しなさい。 下線部 (5)の理由として最も適切なものを, (A)~(D) から選び,記号で答えなさい。 (A) Eating raw chicken eggs or unpeeled fruits can be dangerous in certain conditions because of harmful bacteria or pesticides. (B) Eating unpeeled apples or grapes may cause weight gain. (C) Only young children and elderly people are vulnerable to particular bacteria. (D) Beliefs about what is considered delicious actually come from better understanding of food preparation. 問6 本文の内容と一致するものを, (A)~(G)から3つ選び,記号で答えなさい。 (A) By food preparation processes, the author exclusively means the use of heat. (B) Culturally established ways of consuming food may conflict with scientific principles of food safety. (C) In some food cultures outside Japan, fish in its raw state is not categorized as an edible foodstuff. (D) People having little contact with other cultures tend to view their own food-related conventions as natural and standard. (E) Repeated exercise is required for the mastery of any food preparation. (F) Instinct alone determines what and how people eat. (G) All cultures around the world consider it natural to eat unpeeled fruit.

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