Please complete and submit the History of the Periodic Table Worksheet. Download History of the Periodic Table Worksheet. The PowerPoint in Unit 2 Resources can help you complete this task.

Note: amu stands for atomic mass unit, which is a concept very similar to the atomic mass number but differing slightly. It is a unit for mass of tiny subatomic particles such as protons and neutrons. 1. Given the data in table shown below, calculate the atomic mass of unknown element X. Then, identify the unknown element, which is used medically to treat some mental disorders. 2. Boron has two naturally occurring isotopes: boron- 10 (abundance =19.8%, mass = 10.013amu ); boron-11 (abundance =80.2%, mass =11.009amu ). Calculate the atomic mass of boron. 3. Helium has two naturally occurring isotopes, helium-3 and helium-4. The atomic mass of helium is 3.895 amu. Which isotope is more abundant in nature? Explain. 4. Calculate the atomic mass of magnesium. The three magnesium isotopes have atomic mass and relative abundance of 23.985amu(78.99%),24.986amu(10.00%), and 25.982 amu (11.01\%)