Answer : 1 ) Strontium, 2) Technetium and 3) Silver
Explanation :
Amongst the given options, the most reactive element is strontium, then comes technetium and least reactive is silver. In the reactivity series strontium is a radioactive element with highest reactivity amongst the given choices. It is an alkaline earth metal. Whereas Technetium is little less reactive as compared to strontium. Silver gets the last position as it is least reactive in nature.
