Internal Examination of a Newly Hatched Alligator. A professional can determine the gender of a very small baby alligator, 6 to 10 inches long. One method is to place the creature on its back and hold open his vent with round-tipped tweezers or forceps, with a helper's assistance.
Technetium is the only element below uranium that does not exist on Earth. It is a synthetic (man-made) element produced in a particle accelerator. For many years, chemists knew that an element with atomic number 43 must exist, based on an empty spot in the periodic table.
Technetium Properties. Technetium is a Block D, Group 7, Period 5 element. The number of electrons in each of Technetium's shells is 2, 8, 18, 13, 2 and its electron configuration is [Kr] 4d 5 5s 2. The technetium atom has a radius of 135.2.pm and its Van der Waals radius is 200.pm.