In the beginning of this chapter, Kean starts by describing how scientist eventually began to fill in the gaps on the periodic table. He then introduces Ernest Rutherford and, his student, Henry Mosely from the University of Manchester in England. Mosely became very interested in working with elements by blasting them with electron beams and examining every element up to gold. The striking of an atom takes out one of the atom's electrons and since electrons are attracted to an atom's nucleus it becomes a very violent reaction. When electrons come in to fill the gap, x-rays are released. Mosley figured out the relation between the x-rays, the protons in the nucleus, and the elements atomic number. Mosely figured out the link between the elements place on the periodic table to its atomic number. This solved the problem to why cobalt came before nickel. With the help from his electron gun it help sort out the confusion of the table. He also figured out elements 43, 61, 72, and 75. He was also challenged by many chemist including, Georges Urbain. But later when World War 1 broke out, he enlisted in the king's army. He died in the year 1915 at Gallipoli. To honor Mosely's memory scientist hunted down all the missing elements he pointed out but only one remained, element 61. A team led by Emilio Segre tried to create an artificial sample but gave up until later when scientist from Oak Ridge National Laboratory discovered element 61 from a uranium ore. However, there was little excitement for this discovery but decided to name the element promethium. Scientist began to focus on nuclear science especially after the atomic bomb. However, some parts were confusing since Mosely proved that both lead-204 and lead-205 can have the same positive energy but different atomic weights. For this Kean express a new tool that scientist needed, quantum mechanics.
Kean then describes how scientist began to concentrate on radioactivity. Earnest Rutherford helped name the atomic matter that was discovered into alpha, beta, or gamma decay. Gamma being the most deadliest, emits x-rays. However, this was still confusing for some scientist until, in 1932, James Chadwick discovered the neutral neutrons. Neutrons add weight but have no charge; hence, they are neutral, and this suddenly made sense. Beta decay became the conversion of neutrons to protons, beta decay converts the atom into a different element, and alpha decay also converts the element but tears off 2 neutrons and 2 protons. Later Kean explains the model of atomic innards and that elements remained undiscovered because they were just too unstable that they would deteriorate.
Kean then introduces Leo Szilard who produced the idea of a chain reaction but this required billions of neutrons to travel in one direction. Since plutonium and uranium were dangerous and expensive scientist on the Manhattan Project had to figure out how much they needed to create the bomb. They had to calculate how the neutron collided with the plutonium atom. So they gathered up a bunch of random measurements and assigned these calculations to a bunch of young women, mostly the wives of the scientist. So basically the scientist gathered virtual data for the uranium and plutonium bomb.
Kean then introduces Stanislaw Ulam and John von Neumann discovered the Monte Carlo method after Ulam began writing equations in a journal and connecting them the calculations done in the Manhattan Project. Monte Carlo system sped up the early development of computers and pushed through the next generation of weapons, specifically nuclear. With this method Von Neumann and Ulam created "supers" which were powerful bombs that fused extra-heavy liquid hydrogen.
Kean then concludes with a bomb even bigger than a uranium bomb, a colbalt-60 dirty bomb. The whole purpose of this bomb is to emit gamma rays. The gamma rays would reach the bone marrow and even alter the chromosomes of humans, resulting in cancer and deformities. What's even worse is that Colbalt-60 would settle into the earth and stay there fully armed and would take almost a life time for the ground to recover. So although Colbalt-60 bombs are un-suited for war since they pollute the lands the conquerors would want to live on, "a mad man", as Kean puts it, can wipe out the whole world without caring. Luckily, to the publics knowledge, no such bomb has ever been made and Leo Szilard made sure that the countries stopped their pursuit on nukes when he purposed that idea of a "doomsday device".
This chapter was also interesting; however, I'd sometimes get confused in all the information. But overall I liked the chapter and the interesting stories. The one thing that I would share with a friend is the Colbalt-60 bomb and how powerful its destruction would be.
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