THALLIUM My element was Thallium. It is atomic number 81. It has 81 protons and electrons and 123 neutrons. Thallium has a mass of 204.3833 atomic mass units. Its symbol is Tl. It resides in Group IIIA of the periodic table. That is the aluminum family. Thallium has a bluish color after exposure to the air. It is a very soft and malleable metal. It has an electron configuration of 1s22s23s23p64s23d104p65s24d105…showed first 75 words of 459 total…

…showed last 75 words of 459 total…heart muscle. It is injected into the veins and then a camera records the thallium penetration and shows the areas of the reduced flow of blood.         Thallium is an element that most people have never heard of before, but they will in the future. If the heart exams prove to be beneficial, it should become more popular. Thallium is very dangerous though. It is not very common though and therefore should not be worried about.