Technetium, the element of the week

The last few posts were about elements. I am doing a new thing called "element of the week". I asked my brother to pick out a random element that he had never heard of. I got stuck with technetium. Please do ignore the four of hearts in the corners, I had to scan my periodic table playing cards in order to represent technetium. This darn old playing card just gave away all the facts for you. Its symbol is Tc, its atomic number is 43, It is radioactive, it is- WAIT STOP! there is something unusual here. All elements with atomic numbers over 83 are radioactive. There are only two elements with atomic numbers less than 83 that are radioactive (technetium and promethium). This is odd. Now, back to the facts, it is synthetic, it- STOP AGAIN! Again technetium and promethium (61) are the only synthetic elements until neptunium (93). All the others before 93 are naturally occurring although time to time technetium atoms appear (from the decay of other elements) but break down after about a minute. Technetium's atomic weight is 98.91 and, FYI the atomic weight is the number of protons plus neutrons. You might be thinking "how do you get 0.91 neutrons?". What we do is calculate the average of all the different isotopes of technetium and presto! you end up with the atomic weight. Technetium's melting point (the point when it changes from solid to liquid) is 2,172 degrees Celsius and the boiling point (liquid to gas) is 4,877 degrees Celsius. At the bottom of the card it shows technetium's uses. Medical research and radioactive diagnosis use technetium. Now remember, Tc, and not TCU, the college football team.