An element 'A' reacts with oxygen to form an oxide of the formula `A_2O` which dissolves in dil. HCl. The oxide formed turns red litmus paper blue.
Write the formula of `A_2O` and its reaction with dil. HCl.

An element 'A' reacts with oxygen to form an oxide of the formula A_2O which dissolves in dil. HCl. The oxide formed turns red litmus paper blue. Is the element a metal or a non-metal?

An element x reacts with oxide to from oxide, X_2O which dissolves in water and turns red litmus solution blue, give the nature of oxide and indicate X is metal or non-metal.

An element X shows two valencies i.e. 2 and 4. Write the formula of its oxides.

A substance 'S' is used as a building material and is insoluble in water. When reacted with dil H_2SO_4 it produces a gas 'X' which turned lime water milky. When the liberated gas 'K' passed in excess, the milkiness disappeared. Write the name and chemical formula of S and its reactions will dil H2SO4, name the acid and base from which the substance 'S' is made.

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,

Write the formula of the compounds formed by: NH_4^+ and Cr_2O_7^(2-)

An aqueous solution of metal ion M_1 reacts separately with reagents Q and R in excess to give tetrahedral and square planar complexes, respectively. An aqueous solution of another metal ion M_2 always forms tetrahedral complexes with these reagents. Aqueous solution of M_2 on reaction with reagent S gives white precipitate which dissolves in excess of S. The reactions are summarized in the scheme given below : M1, Q and R , respectively are :

Nitric acid forms an oxide of nitrogen on reaction with P_4O_10 . Write the reaction involved. Also write the resonating structures of the oxide of nitrogen formed.