The number of electronic shells contained in an atom with electron configuration 1s² 2s² 2p6 3s² 3p6 4s² is? by Sunday | Sep 16 | Chemistry JAMB | 0 comments A. 3 B. 2 C. 4 D. 5 Correct Answer: Option C – 4 Users Also Read These:What is the atomic number of an element whose cation…Given that the electronic configuration of an…The electronic configuration of an element is 1S²…How many unpaired electrons are there in an atom of…The electronic configuration of element Z is 1s² 2s²…