MCQ
The nucleus of an element contain $ 9 $ protons. Its valency would be
  • $1$
  • B
    $3$
  • C
    $2$
  • D
    $5$

Answer

Correct option: A.
$1$
a
(a) Since its nucleus contain $9$ proton so its. atomic number is $ 9$ and its electronic configuration is $  2, 7. $ So it require one more electron to complete its octet. Hence its valency is $1.$

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   \,\,\,\,\,Ph\,\,\,\,C{{H}_{3}}  \\
   |\,\,\,\,\,\,\,\,\,\,|\,\,  \\
   Ph-C-C-C{{H}_{3}}  \\
   |\,\,\,\,\,\,\,\,\,\,|\,\,\,  \\
   \,OH\,\,\,OH  \\
\end{matrix}}}\,+\underset{(B)}{\mathop{\begin{matrix}
   \,\,\,\,Ph\,\,\,Et  \\
   \,\,|\,\,\,\,\,\,\,\,\,|  \\
   Ph-C-C-Et  \\
   \,\,|\,\,\,\,\,\,\,\,\,|  \\
   \,\,\,\,\,OH\,\,OH  \\
\end{matrix}}}\,\xrightarrow{{{H}_{2}}S{{O}_{4}}}$

 

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   Ph\,\,\,\,\,O\,  \\
   |\,\,\,\,\,\,\,\,||\,\,  \\
   Ph-C-C-C{{H}_{3}}  \\
   |\,\,\,\,\,\,\,\,\,\,\,\,  \\
   C{{H}_{3}}\,\,\,\,\,\,\,\,  \\
\end{matrix}$                                $(q)$ $\begin{matrix}
   \,Ph\,\,\,\,\,O\,  \\
   \,\,|\,\,\,\,\,\,\,\,||  \\
   Ph-C-C-Et  \\
   |\,\,\,\,\,\,\,\,\,\,  \\
   Et\,\,\,\,\,\,\,\,\,\,  \\
\end{matrix}$

$(r)$ $\begin{matrix}
   \,Ph\,\,\,\,\,O\,  \\
   |\,\,\,\,\,\,\,\,\,\,||\,  \\
   Ph-C-C-C{{H}_{3}}  \\
   |\,\,\,\,\,\,\,\,\,\,\,\,\,\,  \\
   Et\,\,\,\,\,\,\,\,\,\,\,\,\,  \\
\end{matrix}$                             $(s)$ $\begin{matrix}
   \,\,\,Ph\,\,\,\,\,O\,  \\
   \,\,|\,\,\,\,\,\,\,\,||  \\
   Ph-C-C-Et  \\
   |\,\,\,\,\,\,\,\,\,\,  \\
   C{{H}_{3}}\,\,\,\,  \\
\end{matrix}$

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