If an atom has 13 electrons how many electron shells does it have

Explanation:

If an atom has 13 electrons then it belongs to p-block of periodic table.

s level can accommodate 2 electrons.

p level can accommodate 6 electrons.

13 means 1s2 2s2 2p6 3s2 3p1.

As you can see there totally 5 sub-shells.

Total number of shells are 3(1,2,3).

in 1783 cavendish was working with his hydrogen gas and found that when he burned it and condensed the vapor it was water. this was very significant since it disproved the greek theory of elements completely since water was not a simple substance but the product of two gases. it was lavoisier who hearing of the experiment gave cavendish's gas the name hydrogen ("water-producer") and added that hydrogen burned by combining with oxygen and that water was a hydrogen-oxygen combination.

explanation: