(a) State the Modem Periodic Law. How have the element been arranged in the modern periodic table ? Why is it considered that the position of hydrogen in the periodic table is anomalous ?
(b) An element X(2,8,2) combines separately with ${{NO}_{3}}^{-}$ radicals. Write the formulae of the compounds so formed. To which group of the periodic table does the element ‘X’ belong ? Will it form convalent or ionic compounds with these radicals ? How ?
(a) Modem Periodic Law: Properties of elements (both physical and chemical) are the periodic function of their atomic number.
In increasing order of atomic number because hydrogen can be placed in group 1 with alkali metals as well as with halogens in 17th group.
X belongs to 2nd group.
X will form ionic compound because it is a metal and the radicals are of non-metals.