Consider the following data for five hypothetical elements: Q, W, X, Y, and Z. Rank the elements from most reactive to least reactive. Combination Observation of reaction Q+W+ Reaction occurs X+Z+ No reaction W+Z+ Reaction occurs Q++Y Reaction occurs

Y > Q > W > Z > X

Explanation:

Reactivity series gives information on the reactive nature of element. Only more reactive element will replace a less reactive element in it compound. More reactive element usually displace less reactive element in it compound.

From the reaction above Y displace element Q from it compound. Element Q displace W from it compound.  W displace Z in it compound. The element X cannot displace Z from it compound because it is less reactive .Their is no reaction.

Base on the reactivity element  Y is the most reactive.

Y > Q > W > Z > X

c. because step up transformer steps up the input voltage i.e increases the input voltage  

the number of turns are greater on the secondary side of step up transformer  

transformer does not handle dc current