化学のみ：酸とアルコールからエステルが生成する
導入済み| English | 意味 |
|---|---|
| ester/ˈestə/ | エステル |
| esterification/ˌestəˌrɪfɪˈkeɪʃn/ | エステル化反応 |
What would explain this observation?
- Warming ethanol with ethanoic acid under an approved acid-catalysed method can make ethyl ethanoate. The name keeps information about both starting organic compounds.
- Start with a prediction. State the quantities or features you would compare, then decide what evidence could distinguish two explanations.
Build the model
- A carboxylic acid reacts with an alcohol to form an ester 酯 and water. Ethanoic acid plus ethanol forms ethyl ethanoate plus water. A suitable acid catalyst and warming support the laboratory reaction; school demonstrations use a controlled water bath and approved small quantities because the reagents and product can be flammable and concentrated catalyst is hazardous. The course requires the ester name ethyl ethanoate, not a memorised list of other ester names.
- ester: An organic compound containing the C(=O)–O–C connection formed here from an acid and alcohol; esterification 酯化反应: Reaction of a carboxylic acid with an alcohol to form an ester and water.
乙酸とエタノールが反応して何ができるか。
難易度 1/5 · 100 コイン + 今日初回完了時に小ボーナス付与
酸＋アルコール＝エステル＋水：エタン酸とエタノールはエチルエタン酸エステルと水を形成します。二酸化炭素、アルカンまたは水素は関与しません。
各専門用語を正確な意味と対応させよ。
難易度 2/5 · 140 コイン + 今日初回完了時に小ボーナス付与
関連する物理量やプロセスを区別するために定義を使用せよ。
Choose evidence that can test it
- The illustrated product contains a C(=O)–O–C connection. The acid-derived carbon framework and alcohol-derived carbon framework both remain. It is different from simply mixing an acid with water, from sodium carbonate reaction and from alkene addition. Formation need not be complete in one trial. A characteristic smell may be supplied as reference evidence but is not a unique identification test or a reason to inhale concentrated vapour.
- Use the word equation and the displayed model to trace carbon and oxygen atoms. In an approved teacher-led demonstration, record the starting reagents, warming/catalyst conditions and evidence without treating a fruity description alone as conclusive. A comparison may use supplied spectra or labelled products if no practical is approved. Do not improvise a flame, sealed heated vessel, concentrated acid addition or consumption of the product. Actual school evidence remains separate from written practice.
この場合、調査やモデルをより妥当にする2つの習慣は何か。
難易度 2/5 · 140 コイン + 今日初回完了時に小ボーナス付与
条件や仮定を明記することで他者が正確に再現でき、根拠となる証拠を記録することで結論を検証できます。相反する結果を隠すと、誤った結論を疑う証拠を失いますし、単一の測定でより広い主張を成立させることはできません。
Work from known quantities
- State the known values and their units. Choose the relation because its assumptions fit this case, then rearrange before substitution.
- Known: ethanol has two carbon atoms and ethanoic acid has two, so ethyl ethanoate has four. Its molecular formula C₄H₈O₂ has fourteen atoms: 4+8+2=14. The remaining atoms form water in the model. Two represented ester molecules contain 28 atoms. The word equation is sufficient for the acquired acid-reaction requirement; balanced symbol-equation recall is not imposed.
Ethyl ethanoate is C₄H₈O₂. Find the total atoms in three represented molecules. Use the same sequence: known quantities → model → relation → substitution → unit and interpretation.
アセト酸エチルの分子式は C₄H₈O₂ である。表された3つの分子に含まれる総原子数を求めよ。
難易度 2/5 · 140 コイン + 今日初回完了時に小ボーナス付与
結果は 42 個の原子です。既知：エチルエタン酸エステル C4H8O2 は 4 + 8 + 2 = 14 個の原子を分子あたり含みます。3つの分子の場合：3 × 14 = 42 個の原子です。
Check the conclusion and its limits
- Do not confuse the acid catalyst with a substance consumed in the overall word equation, or name the product ethanol because an alcohol was used. An ester is not the same functional group as its parent acid. The water product does not prove every condensation process or polymer structure has been taught; those are separate 4.7.3 requirements.
- Return to the original observation. Explain what the result supports, which conditions it assumes, and one way to test a competing explanation.
An esterification product must retain the starting acid’s OH group unchanged. This claim is false: In esterification the acid's OH leaves with the alcohol's H to form WATER; the ester link C(=O)-O is newly formed. Retaining the acid's OH unchanged would leave a carboxylic acid, not an ester.
Chemistry-only: an acid and an alcohol form an ester: The illustrated product contains a C(=O)–O–C connection. The acid-derived carbon framework and alcohol-derived carbon framework both remain. It is different from simply mixing an acid with water, from sodium carbonate reaction and from alkene addition. Formation need not be complete in one trial. A characteristic smell may be supplied as reference evidence but is not a unique identification test or a reason to inhale concentrated vapour.
エステル化生成物は、出発物質である酸のOH基をそのまま保持しなければならない。
難易度 1/5 · 100 コイン + 今日初回完了時に小ボーナス付与
エステル化反応において、酸のOHとアルコールのHが結合して水が生成され、エステル結合C(=O)-Oが新たに形成されます。酸のOHをそのまま残すと、エステルではなくカルボン酸が残ってしまいます。
ここで酸とアルコールから形成されるC(=O)–O–C結合を含む有機化合物：その専門用語を記せ。
難易度 1/5 · 100 コイン + 今日初回完了時に小ボーナス付与
エステルとは、酸とアルコールから形成されるC(=O)–O–C結合を含む有機化合物のことである。