Question

Neon and chlorine have atomic numbers $10$ and $17$ respectively. Their valencies will be ______ and ______ respectively.

• A. $1,1$
• B. $1,0$
• C. $0,1$
• D. $0,0$

Answer 1

Answer: (C)

$0,1$

Valency of $Ne$ is zero as it is a noble gas and thus does not take part in bond formation. $Cl$ has electronic configuration: $2,8,7$. Therefore, $Cl$ will accept one electron to attain stable noble gas configuration. Thus valency of $Cl$ is $1$.