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When the re­ac­tion dies down, the mix­ture is heat­ed un­til the smell of the ni­tro com­pound dis­ap­pears. Re­duc­tion of the ni­tro group: a few crys­tals or drops of ni­tro com­pounds are mixed with 0.5 M HCl, and metal­lic zinc is added. This re­ac­tion can be re­gard­ed as the re­duc­tion of zinc ions via elec­trol­y­sis. For ex­am­ple, if the so­lu­tion con­tains a zinc salt, then the zinc ions pre­cip­i­tate on the cath­ode (the elec­trode to which elec­trons flow) as metal­lic zinc. through an elec­trolyte so­lu­tion, chem­i­cal re­ac­tions take place on the elec­trodes, and the de­gree of the trans­for­ma­tion of this re­ac­tion is con­nect­ed with the amount of elec­tric­i­ty ac­cord­ing to Fara­day’s laws of elec­trol­y­sis. When an elec­tric cur­rent is passed through a so­lu­tion con­tain­ing ions, i.e. The re­leased mag­ne­sium hy­drox­ide ab­sorbs the com­plex of zinc and ben­zoin, and the pre­cip­i­tate glows green when ex­posed to ul­tra­vi­o­let rays. So­lu­tions of sodi­um thio­sul­fate, sodi­um sil­i­cate, mag­ne­sium chlo­ride, and ben­zoin in ethyl al­co­hol are grad­u­al­ly added to the test so­lu­tion. Ball-and-stick model of the (S)-benzoin molecule Zinc ions were dis­cov­ered based on zinc's re­ac­tion with ben­zoin. Ex­am­ples of sev­er­al re­ac­tions with zinc When re­act­ing with al­ka­lis, the el­e­ment forms com­plex com­pounds known as hy­droxo-zin­cates. Zinc re­acts with both acids and al­ka­lis, mak­ing it an am­pho­ter­ic met­al.

Ad­di­tion­al­ly, zinc re­acts with halo­gens, oxy­gen, chalco­gens, al­ka­lis, acids, am­mo­nia and am­mo­ni­um salts, and even with less ac­tive met­als.

In or­di­nary con­di­tions, zinc re­acts rapid­ly with air, grad­u­al­ly form­ing a dull grey zinc ox­ide coat­ing. high heat ca­pac­i­ty and heat con­duc­tiv­i­ty.

at tem­per­a­tures above 200 ☌, los­es its elas­tic­i­ty and be­comes a grey pow­der.elas­tic­i­ty and mal­leabil­i­ty in­crease when heat­ed to ap­prox­i­mate­ly 100 ☌.