(a) What were the two achievements of Mendeleev's periodic table? What was the basis of classification of elements in it?(b) An element X (2, 8, 2) combines separately with (NO3)−, (SO4)2− and (PO4)3− radicals.(c) To which group of the periodic table does the element 'X' belong? Will it form covalent or ionic compound? Why?(d) To which period of the periodic table does the element X belong? Give reason for your answer.(e) Write the name and symbol of element X. Also give the name and symbol of another element which belongs to the same period as element X.

(a) What were the two achievements of Mendeleev's periodic table? What

1.	(a) What were the two achievements of Mendeleev's periodic table? What was the basis of classification of elements in it?(b) An element X (2, 8, 2) combines separately with (NO3)−, (SO4)2− and (PO4)3− radicals.(c) To which group of the periodic table does the element 'X' belong? Will it form covalent or ionic compound? Why?(d) To which period of the periodic table does the element X belong? Give reason for your answer.(e) Write the name and symbol of element X. Also give the name and symbol of another element which belongs to the same period as element X.
Answer» (a) What were the two achievements of Mendeleev's periodic table? What was the basis of classification of elements in it? (b) An element X (2, 8, 2) combines separately with (NO₃)⁻, (SO₄)²⁻ and (PO₄)³⁻ radicals. (c) To which group of the periodic table does the element 'X' belong? Will it form covalent or ionic compound? Why? (d) To which period of the periodic table does the element X belong? Give reason for your answer. (e) Write the name and symbol of element X. Also give the name and symbol of another element which belongs to the same period as element X.