Explain the reason for classifying the periodic table into blocks

The long form of the periodic table divides the elements into four major blocks known as s, p, d, and f.

The period to which a given element belongs can easily be determined from its electron configuration. Based on electron configurations, the periodic table can be divided into blocks denoting which sublevel is in the process of being filled.

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they are both synthetic elements

explanation:

d

answer:

technetium is the most reactive. this is followed by silver. the least reactive out of these three elements is strontium.