13. Which of the following equations represents an oxidation-reduction reaction? NaOH(aq)+HCl(aq)rightarrow NaCl(aq)+H_(2)O(l) E Mg(s)+ZnCl_(2)(aq)rightarrow Zn(s)+MgCl_(2)(aq) E 2HCl(aq)+Ba(OH)_(2)(aq)rightarrow BaCl_(2)(aq)+2H_(2)O(l) E 2AgNO_(3)(aq)+Na_(2)CrO_(4)(aq)rightarrow Ag_(2)CrO_(4)(s)+2NaNO_(3)(aq) E

The correct answer is B: $Mg(s)+ZnCl_{2}(aq)\leftrightarrow Zn(s)+MgCl_{2}(aq)$<br /><br />Explanation:<br />An oxidation-reduction (redox) reaction involves the transfer of electrons between two species. In the given options, only option B represents a redox reaction.<br /><br />In option B, magnesium (Mg) is oxidized, losing electrons to form Mg2+ ions, while zinc (Zn) is reduced, gaining electrons to form Zn metal. This is a redox reaction because there is a change in the oxidation states of the elements involved.<br /><br />The other options do not represent redox reactions. They are either acid-base reactions (option A and C) or precipitation reactions (option D).