Chọn đáp án là: D
Phương pháp giải:
\(\begin{gathered}
Al - 3{\text{e}} \to \mathop {Al}\limits^{ + 3} + 3N{O_3}^ - \hfill \\
x\,\,\,\,\,\,\,\,\,\,3{\text{x}}\,\,\,\,\,\,\,\,\,\,\,\,{\text{ }}\,{\text{ 3x}} \hfill \\
Ag - 1{\text{e}} \to \mathop {Ag}\limits^ + + N{O_3}^ - \hfill \\
y\,\,\,\,\,\,\,\,\,\,y\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,y \hfill \\
\mathop N\limits^{ + 5} + 3{\text{e}} \to \mathop N\limits^{ + 2} O \hfill \\
\,\,\,\,\,\,\,\,\,\,0,6\,\,\,\,\,\,\,\,0,2 \hfill \\
\end{gathered} \)
mKl = 27x+108y =35,1 (1)
ĐLBT số mol e ⇒ 3x+y=0,6(2)
⇒ x,y
⇒ mmuối = mKl + mNO3(muối)
Lời giải chi tiết:
\(\begin{gathered}
Al - 3{\text{e}} \to \mathop {Al}\limits^{ + 3} + 3N{O_3}^ - \hfill \\
x\,\,\,\,\,\,\,\,\,\,3{\text{x}}\,\,\,\,\,\,\,\,\,\,\,\,{\text{ }}\,{\text{ 3x}} \hfill \\
Ag - 1{\text{e}} \to \mathop {Ag}\limits^ + + N{O_3}^ - \hfill \\
y\,\,\,\,\,\,\,\,\,\,y\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,y \hfill \\
\mathop N\limits^{ + 5} + 3{\text{e}} \to \mathop N\limits^{ + 2} O \hfill \\
\,\,\,\,\,\,\,\,\,\,0,6\,\,\,\,\,\,\,\,0,2 \hfill \\
\end{gathered} \)
mKl = 27x+108y =35,1 (1)
ĐLBT số mol e ⇒ 3x+y=0,6(2)
⇒ x= 0,1, y=0,3
⇒ mmuối = mKl + mNO3(muối) = 35,1+ 62.(3.0,1+0,3)=72,3 gam
Đáp án D