Complete the following nuclear equations: When doing these equations you are obeying the law of conservation of mass and charge. What this means is that the sum of top numbers (masses) on the left side must equal the sum of the masses on the right. It also means the sum of the bottom numbers (charges) on the left equal the sum of the charges on the right. The charge (atomic number) of the isotope determines the element. Look on the periodic table to find the identity of the element. 1. Li e + 4H2 + 15 3. Con "e_ + 4. 97Tc43 + e 5.99Tc 43 b+ 6. 239 Pu94 a+