Cho các chất có công thức cấu tạo thu gọn sau: (1) CH3CH2COOCH3 ; (2) CH3OOCCH2CH3; (3) HCOOC2H5; (4) CH3COOH; (5) H3CCOOCH3; (6) HOOCCH2CH2OH; (7) CH3OOC – COOC2H5. Những chất thuộc loại Est

Đáp án đúng là: B

(1) $\text{C}\text{H}{}_3\text{C}\text{H}{}_2\text{C}\text{O}\text{O}\text{C}\text{H}{}_3$: Ester ($\text{m}\text{e}\text{t}\text{h}\text{y}\text{l}\text{p}\text{r}\text{o}\text{p}\text{i}\text{o}\text{n}\text{a}\text{t}\text{e}$)

(2) $\text{C}\text{H}{}_3\text{O}\text{O}\text{C}\text{C}\text{H}{}_2\text{C}\text{H}{}_3$: Ester ($\text{m}\text{e}\text{t}\text{h}\text{y}\text{l}\text{p}\text{r}\text{o}\text{p}\text{i}\text{o}\text{n}\text{a}\text{t}\text{e}$, viết ngược)

(3) $\text{H}\text{C}\text{O}\text{O}\text{C}{}_2\text{H}{}_5$: Ester ($\text{e}\text{t}\text{h}\text{y}\text{l}\text{f}\text{o}\text{r}\text{m}\text{a}\text{t}\text{e}$)

(4) $\text{C}\text{H}{}_3\text{C}\text{O}\text{O}\text{H}$: Carboxylic acid ($\text{a}\text{c}\text{e}\text{t}\text{i}\text{c}\text{a}\text{c}\text{i}\text{d}$)

(5) $\text{H}{}_3\text{C}\text{C}\text{O}\text{O}\text{C}\text{H}{}_3$: Ester ($\text{m}\text{e}\text{t}\text{h}\text{y}\text{l}\text{a}\text{c}\text{e}\text{t}\text{a}\text{t}\text{e}$)

(6) $\text{H}\text{O}\text{O}\text{C}\text{C}\text{H}{}_2\text{C}\text{H}{}_2\text{O}\text{H}$: Tạp chức (acid + alcohol)

(7) $\text{C}\text{H}{}_3\text{O}\text{O}\text{C}\text{–}\text{C}\text{O}\text{O}\text{C}{}_2\text{H}{}_5$: Ester hai chức

⇒ Các chất thuộc loại Ester: (1), (2), (3), (5), (7).