Question

What is the change in oxidation number of carbon in the following reaction?
$C{H}_4\left(g\right)+4C{l}_2\left(g\right)\to CC{l}_4\left(l\right)+4HCl\left(g\right)$

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• A. 0 to -4
• B. 0 to +4
• C. -4 to +4
• D. +4 to +4

Answer 1

The correct option is C -4 to +4

(I) $C{H}_4$
$\Rightarrow x+4=0$
$\Rightarrow x=-4$
Oxidation number of C in $C{H}_4$ is −4.

(II) $CC{l}_4$
$\Rightarrow x-4=0$
$\Rightarrow x=+4$
Oxidation number of C in $CC{l}_4$ is +4.
Therefore, change in oxidation state of carbon is from −4 to +4.