Direction: Write your answer in the space provided. 1.U-235 is a different isotope of uranium. It has its own decay series as it too eventually changes to lead. Give the U-235 decay series a try and practice your skills. (Use another sheet of paper for your answer) 2. What happens to Ra-228? Write element missing. 228 Ra 88 (beta particle) Balance the mass numbers and the atomic numbers, be careful of that -1) 3. CHECK THE PERIODIC TABLE. The new isotope has a mass number of 228 and an atomic number of 88. 228 ? 88 each element has a unique atomic number The new isotope is -228 which is a beta emitter. 4. Why do scientists study and synthesize new transuranium elements in the laboratory? What are the uses of these elements? Create a timeline using illustrations and text showing on how elements form with the concept of atomic number