which of the following is not an oxidation - reduction reaction?\no xef6(s)→xef4(s)+f2(g)\no…

Explanation:

Step1: Recall oxidation - reduction reaction criteria

Oxidation - reduction reactions involve a change in oxidation numbers of elements.

Step2: Analyze first reaction

In $XeF_{6}(s)\rightarrow XeF_{4}(s)+F_{2}(g)$, the oxidation number of $Xe$ changes from + 6 in $XeF_{6}$ to + 4 in $XeF_{4}$ and the oxidation number of $F$ changes, so it is a redox reaction.

Step3: Analyze second reaction

In $2Cs(s)+I_{2}(g)\rightarrow 2CsI(s)$, $Cs$ goes from 0 to + 1 oxidation state and $I$ goes from 0 to - 1 oxidation state, so it is a redox reaction.

Step4: Analyze third reaction

In $2H_{2}SO_{4}(aq)+2Ba(OH){2}(aq)\rightarrow 2BaSO{4}(s)+4H_{2}O(l)$, this is a double - displacement reaction. The oxidation numbers of $H$, $S$, $O$, $Ba$ remain the same throughout the reaction. $H$ is + 1, $S$ is + 6, $O$ is - 2 and $Ba$ is + 2. So it is not a redox reaction.

Step5: Analyze fourth reaction

In $Zn(s)+2AgNO_{3}(aq)\rightarrow Zn(NO_{3})_{2}(aq)+Ag(s)$, $Zn$ goes from 0 to + 2 oxidation state and $Ag$ goes from + 1 to 0 oxidation state, so it is a redox reaction.

Answer:

$2H_{2}SO_{4}(aq)+2Ba(OH){2}(aq)\rightarrow 2BaSO{4}(s)+4H_{2}O(l)$