Question

How many
element are present in 4thand
5th
period?

Answer 1

Answer:

The fifth period contains 18 elements, beginning with rubidium and ending with xenon. As a rule, period 5 elements fill their 5s shells first, then their 4d, and 5p shells, in that order; however, there are exceptions, such as rhodium.

Explanation:

This is the answer.

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