Question

Which reaction will not occur out of the following

• A. $Fe + H _{2} SO _{4} \longrightarrow H _{2}+ FeSO _{4}$
• B. $Cu +2 AgNO _{3} \longrightarrow Cu \left( NO _{3}\right)_{2}+2 Ag$
• C. $2 KBr + I _{2} \longrightarrow 2 Kl + Br _{2}$
• D. $CuO + H _{2} \longrightarrow Cu + H _{2} O$

Answer 1

Answer: (C)

$2 KBr + I _{2} \longrightarrow 2 KI + Br _{2}$

reaction is not possible. Reaction of potassium bromide with iodine gives no product, as the activity of halogens decreases down the group. Hence, iodine is less reactive than bromine and thus, it cannot displace bromine from its compounds.

$KBr + I _{2} \longrightarrow $ No reaction

Reaction of copper with silver nitrate is possible, as copper is more reactive than silver, so it can displace silver from its salt solution.

$Cu + 2AgNO_3 \longrightarrow Cu(NO_3)_2 + 2Ag$

Reaction of iron with sulphuric acid is also possible as iron is placed above hydrogen is activity series and thus can displace hydrogen from dilute acid like $H_2SO_4,\, HCl$.

$Fe + H_2SO_4 \longrightarrow H_2 + FeSO_4$

$CuO+H_2 \longrightarrow Cu + H_2O$; is a redox reaction, that proceeds via electrolysis.