Question

The following facts are available :

$2A^{\ominus }+B_2\to 2B^{\ominus }+A_2$;
$2C^{\ominus }+B_2\to Noreaction$;
$2D^{\ominus }+A_2\to 2A^{\ominus }+D_2$
Which of the following statements is correct ?

• A. $E_{C^{\ominus }|C_2}^{\ominus }>E_{B^{\ominus }|B_2}^{\ominus }>E_{A^{\ominus }|A_2}^{\ominus }>E_{D^{\ominus }|D_2}^{\ominus }$
• B. $E_{C^{\ominus }|C_2}^{\ominus }<E_{B^{\ominus }|B_2}^{\ominus }<E_{A^{\ominus }|A_2}^{\ominus }<E_{D^{\ominus }|D_2}^{\ominus }$
• C. $E_{C^{\ominus }|C_2}^{\ominus }<E_{B^{\ominus }|B_2}^{\ominus }>E_{A^{\ominus }|A_2}^{\ominus }>E_{D^{\ominus }|D_2}^{\ominus }$
• D. $E_{C^{\ominus }|C_2}^{\ominus }>E_{B^{\ominus }|B_2}^{\ominus }<E_{A^{\ominus }|A_2}^{\ominus }<E_{D^{\ominus }|D_2}^{\ominus }$

Answer 1

The correct option is B $E_{C^{\ominus }|C_2}^{\ominus }<E_{B^{\ominus }|B_2}^{\ominus }<E_{A^{\ominus }|A_2}^{\ominus }<E_{D^{\ominus }|D_2}^{\ominus }$

$2A^{\ominus }+B_2\to 2B^{\ominus }=A_2$;
$2C^{\ominus }+B_2\to Noreaction$;
$2D^{\ominus }+A_2\to 2A^{\ominus }+D_2$

Examples are of non-metals. A non-metal having higher reduction potential replaces the other from its solution.

Thus, $E_{R{P}_D}^{\ominus }<E_{R{P}_A}^{\ominus }<E_{R{P}_B}^{\ominus }$
Thus, $E_{O{P}_D}^{\ominus }>E_{O{P}_A}^{\ominus }>E_{O{P}_B}^{\ominus }$.

Thus, only choice is (b) because $E_{O{P}_B}^{\ominus }<E_{O{P}_C}^{\ominus }$ as B replaces C from solution.