CHY 104 Lecture Notes - Polonium, Silicate Minerals, Gallium
14 Jan 2013
School
Department
Course
Professor
Document Summary
Mendeleyv"s left many vacant spaces for the still unknown elements. For example, next to calcium (40) should be titanium (48) but it resembled silicon (28) instead of aluminium (27). He left vacant space for element with atomic mass 44. Mendeleyv"s discovered new elements and also guessed their atomic mass and properties. Mendeleyv"s corrected the atomic masses of certain elements on basis of their properties and provided proper place to them in the periodic table. According to mendeleyv"s periodic law potassium (39) should be placed before argon (40) but he placed. Argon (40) before potassium (39) which goes against his law. Mendeleyv"s periodic table gives no indication about the position of isotopes. Mendeleyv"s periodic table gives no idea about structure of atoms. Lanthanides and actinides have not been given proper place in periodic table. Alkali metals and coinage metals with different properties are placed in the same group. This defect has been replaced by placing them into two sub groups.
