Element 'X' forms a chloride with the formula `XCl_2` Which is a solid with a high melting point, X would most likely be in the same group of the periodic table as:
Na, Mg, Al, Si,

What is the formula of a Compound in which the element Y forms hcp lattice and atoms of X occupy 2/3 rd of tetrahedral voids?

Two elements X and Y have atomic numbers 12 and 16 respectively. Write the electronic configuration for these elements. To which period of the modern perioidic table to these two elements belong? What type of bond will be formed between them and why?

A substance X, which is an oxide of a group 2 element, is used intensively in the cement industry. This element is presented in bones also. On treatment with water it forms a solution which turns red litmus blue. Identify X and also write the chemical reactions involved.

Write the names and symbols of two most reactive metals belongiong to group I of the periodic table. Explain by drawing electronic structure how either one of the two metals reacts with halogen. With which name is the bond formed between these elements known and what is the class of the compuond so formed known? state any four physical properties of such compounds.