The Lithium atom has only two energy levels. The third is empty. Therefore, we can refer to the second energy level of the lithium atom as the outermost level. The electrons in this outermost energy level are called valence electrons. Refer to the table you just constructed, and determine the number of valence electrons for the first 18 elements. Fill in the table with the identified number of valence electrons Type the correct answer in each box. Use numerals instead of words.