What is the electron configuration of a chlorine ion in a compound of becl2? a. [2.8.7]- b. [2.8.8]- c. [2.8.8]+ d. 2.8.7

Chlorine has 7 valence electrons in the outermost shell. when it forms an ionic bond with Be, it takes in 1 electron and achieves the noble gas configuration
since it has one more electron it gains a negative charge of -1.
anion is then - Cl⁻
electronic configuration of Cl atom is - [2,8,7]
after taking in the electron Cl⁻ - [2,8.8]⁻
answer is 
B. [2.8.8]⁻

A. volume stays constant. just took took the quiz

Your answer is a just took the test