Look at where the notes fall on the first three frets of the guitar, then the next five, and then the next four. The first string position being âopen,â the first four frets of the guitar neck are shown. The notes of the fourth through eighth frets.
The greatness of Mendeleev was that not only did he leave spaces for elements that were not yet discovered but he predicted properties of five of these elements and their compounds. How foolish he would have seemed if these predictions had been incorrect but fortunately for him three of these missing elements were discovered by others within 15 years (ie within his lifetime).
Mendeleev realized that the physical and chemical properties of elements were related to their atomic mass in a 'periodic' way, and arranged them so that groups of elements with similar properties fell into vertical columns in his table.e was also able to work out the atomic mass of the missing elements, and so predict their properties. And when they were discovered, Mendeleev turned out to be right. For example, he predicted the properties of an undiscovered element that should fit below aluminum in his table.