Thực hiện các thí nghiệm sau: (a) Nung nóng C u ( N O 3 ) 2 . (b) Cho F e ( O H ) 2 vào dung dịch H 2 S O 4 đặc, nóng (dư). (c) Sục khí C O 2

Đáp án đúng là: B

(a) $2\text{C}\text{u}\left(\text{N}\text{O}{}_3\right){}_2\stackrel{t^o}{\to }2\text{C}\text{u}\text{O}+4\text{N}\text{O}{}_2\uparrow +\text{O}{}_2\uparrow .$

→ Thỏa mãn.

(b) $2\text{F}\text{e}(\text{O}\text{H}){}_2+4\text{H}{}_2\text{S}\text{O}{}_{4\text{(}đ)}\stackrel{t^o}{\to }\text{F}\text{e}{}_2\left(\text{S}\text{O}{}_4\right){}_3+\text{S}\text{O}{}_2\uparrow +6\text{H}{}_2\text{O}.$

→ Thỏa mãn.

(c) $\text{C}\text{O}{}_2+\text{C}\text{a}(\text{O}\text{H}){}_2\to \text{C}\text{a}\text{C}\text{O}{}_3\downarrow +\text{H}{}_2\text{O}.$

→ Không thỏa mãn.

(d) $2\text{K}\text{H}\text{S}\text{O}{}_4+2\text{N}\text{a}\text{H}\text{C}\text{O}{}_3\to \text{K}{}_2\text{S}\text{O}{}_4+\text{N}\text{a}{}_2\text{S}\text{O}{}_4+2\text{C}\text{O}{}_2\uparrow +2\text{H}{}_2\text{O}.$

→ Thỏa mãn.

(e) $3\text{F}\text{e}{}^{2+}+4\text{H}{}^{+}+\text{N}\text{O}{}_3^{-}\to 3\text{F}\text{e}{}^{3+}+\text{N}\text{O}\uparrow +2\text{H}{}_2\text{O}.$

→ Thỏa mãn.

(g) $\text{F}\text{e}+\text{H}{}_2\text{S}\text{O}{}_4\to \text{F}\text{e}\text{S}\text{O}{}_4+\text{H}{}_2\uparrow .$

→ Thỏa mãn.