Account for the' "play of-colours' shown by. sodium thiosulphate with-silver' nitrate.

Explanation

a. Yes
b. Physical state of the catalyst is differént from that of the reáctants.
.Delta H=-196.6 KJ.
.V_2 O_5., is a solid.
Ass an exothermic reaction it is to be done at. an optimum" temperature. As the volume. decreases in. the forward reaction, use high pressue to get good yield of .SO_y.. Thus-Le-Chatelier principle is applied.

Na_2 ~S_2 O_s+2 AgNO_3 rarr 2 NaNO_3+Ag_2 ~S_2 O_3
white
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