which of the following is not an oxidation - reduction reaction?\no xef₆(s) → xef₄(s) + f₂(g)\no 2cs(s) +…

Explanation:

Step1: Recall oxidation - reduction reaction concept

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

Step2: Analyze first reaction

For $\text{XeF}_6(s)\to\text{XeF}_4(s)+\text{F}_2(g)$, Xe changes from +6 in $\text{XeF}_6$ to +4 in $\text{XeF}_4$ and F changes from - 1 in $\text{XeF}_6$ to 0 in $\text{F}_2$, so it is a redox reaction.

Step3: Analyze second reaction

For $2\text{Cs}(s)+\text{I}_2(g)\to2\text{CsI}(s)$, Cs changes from 0 to +1 and I changes from 0 to -1, so it is a redox reaction.

Step4: Analyze third reaction

For $2\text{H}_2\text{SO}_4(aq)+2\text{Ba(OH)}_2(aq)\to2\text{BaSO}_4(s)+4\text{H}_2\text{O}(l)$, this is a double - displacement reaction. Oxidation numbers of H (+1), S (+6), O (-2), Ba (+2) remain the same throughout the reaction. So it is not a redox reaction.

Step5: Analyze fourth reaction

For $\text{Zn}(s)+2\text{AgNO}_3(aq)\to\text{Zn(NO}_3)_2(aq)+\text{Ag}(s)$, Zn changes from 0 to +2 and Ag changes from +1 to 0, so it is a redox reaction.

Answer:

$2\text{H}_2\text{SO}_4(aq)+2\text{Ba(OH)}_2(aq)\to2\text{BaSO}_4(s)+4\text{H}_2\text{O}(l)$