7. Which two of the following elements in the ground state at the outer level contain an equal (=identical) number of -electrons and p -electrons? 1) C 2) Te 3) Be 4) Sn 5) Ge Answer (score:1):

The correct answer is 3) Be and 5) Ge.<br /><br />Explanation:<br />In the ground state, the number of s-electrons and p-electrons in an atom's outermost shell determines its chemical properties. For an element to have an equal number of s-electrons and p-electrons in its outermost shell, it must have a total of 4 electrons in that shell.<br /><br />1) Carbon (C) has 2 s-electrons and 2 p-electrons in its outermost shell.<br />2) Tellurium (Te) has 2 s-electrons and 6 p-electrons in its outermost shell.<br />3) Beryllium (Be) has 2 s-electrons and 2 p-electrons in its outermost shell.<br />4) Tin (Sn) has 2 s-electrons and 10 p-electrons in its outermost shell.<br />5) Germanium (Ge) has 2 s-electrons and 6 p-electrons in its outermost shell.<br /><br />Therefore, the elements with an equal number of s-electrons and p-electrons in their outermost shell are Beryllium (Be) and Germanium (Ge).