2 8 1 element July 8, 2019 16 32 64 128 2 8 1 element name 2 8 18 1 element 2 8 1 химический элемент 2 8 1 electron configuration element 2 8 1 to which period does this element belong Which element has 2 8 1 Element with configuration 2 8 1 Element with structure 2 8 1 2 8 18 2 element
