InterviewSolution
Saved Bookmarks
InterviewSolution
| 1. |
Mendeleev classified the elements and arranged them in the form of a table. Hydrogen whichresembles alkali metalsand halogens, was placed along with the alkali metals in the first group.Why? How does it resemble halogens? Why do you think he named it as Periodic Table? |
|
Answer» Hydrogen is the first element of the periodic table & often called protium. Its electronic configuration is [1s1]. Due to the presence of only one electron in its 1s shell, hydrogen exhibits a dual behaviour, i.e., it resembles both alkali metals and halogens. As a result, it is placed at the top of the alkali metals in group 1 & also along the halogens in group 17 since just like halogens, it also requires anyone electron to have the configuration of the nearest noble gas element.The dual nature of hydrogen can be justified by the following points: 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.In a periodic way as rows and columns. So he called it a periodic table. |
|