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化学 高校生

波線部の「塩化ナトリウムのように分子とよべるユニットが見当たらないような物質」とはどういうことでしょうか。

STAGE 3分子量と式量 の別冊 p.5~7 o 物質の元素構成を元素記号で表したものを化学式といいます。 原子が特定の chemical forimula みんし ぶんし 比率で結合してできた複合的な粒子を分子といい, 分子を表した化学式を分子 molecule molecular formula しき 式といいます。 例えば、水という物質を構成している基本粒子は, 水素原子2つと酸素原子 1つが集まってできた水分子で,分子式では H.O と表します。 『H.O』と書く 拡大 1は省略 また,ダイヤモンドのような超巨大分子や,塩化大トリウムのように分子と よべるユニットが見当たらないような物質を化学式で表す場合は, 一般に元素 の組成を最も簡単な整数比で表します。 これは組成式とよばれています。 そ せいしき Compositional formula ダイヤモンドは炭素1つ, 塩化ナトリウムはナトリウムと塩素1つずつで, 最も簡単な物質の組成単位なので, 次のように表します。 拡大 『C』と書く ダイヤモンド 拡大 『NaCl』と書く 塩化ナトリウム の結晶 原子量の値を用いて, 分子1個の相対質量や組成式1単位分の相対質量を表 したものを化学式量といい, 前者を分子量, 後者を式量といいます。 ぶん しりょう しきりょう molecular weight formula weight chemical formula weight 03 物質量 21

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英語 高校生

答え4だったのですが何故ですか?

たo/@Ve/ YOの bee ]ast 200 years, people have begun to live longer and longer. This trend more_economnically developed countries。and for some time there Was a growng gap _between_the average_length of jife in rich countries and poor countries/Oyer the Dast few decades、however。 many Poor countries have also made improvements and they are now close to catching up with the wealthier ones. As a result every year there is a 8rowing number of older people in countries all over the world. It is a good thing that people are living longer, but it does have some diffcult aSpects. One of these is that more and more people are suffering from diseases aSsociated with getting older. The number of cases of high blood pressure, heart disease, cancer, and other inesses is increasing, In Australia, for instance。 a recent report said fhat people, on average, live 25 years longer than fhey did a hundred years ago.| Now, there are many more people suffering from serious illnessesOne consequence 3S that each year countries have to spend more and more on medical care foOr Older People. 4 IMany governments have begun to promote healthier lifestyles fo young people, such as losing weight and exercising regularly。as a Way to preventiSerious illnesses、 However as the body gets older, even people who haw have lived healthily are Hikely to become 井. Recentiy。research has begun 10 shoW that 了 this is the result of people's DNA gsetting older. When DNA breaks down, Important iR to control the body's functions is lost. Eventually, serious imesses mmay OCCUT However, David Sinclair,a researcher at the University oNew South Wales im Australia,、 is working on a way to keep DNA healthy。 He used a chemical called nicotinamide mononucleotide (NMN) to see 辻 he could reduce the efects of age on mice. Mice thaf were given NMN became stronger and healthier than they, had been Showing that the chemical was effective./He believes that one day this Lco both longer and make a medicine_for_hunaans. In this Way, Old people may be able to 1 healfhier lives.

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