Manganese forms non-stoichiometric oxides having the gereral formula formula `MnO_x`. The value of `x` for the compound that analyzed `64%` by mass mn :

The oxidation number of Mn in the product of alkaline oxidative fusion of MnO_2 is + x. The value of x is

The formula of an acid is HXO_2 . The mass of 0.0242 moles of the acid is 1.657g . What is the atomic mass of X ?

In a face centred lattice of X and Y, X atoms are present at the corners while Y atoms are at face centres What should be the formula of the compound if: one of the X atoms from a corner is replaced by Z atoms (also monovalent)?

In a face centred lattice of X and Y, X atoms are present at the corners while Y atoms are at face centres What should be the formula of the compound if: two atoms of X are missing from the corner?

In a face centred lattice of X and Y, X atoms are present at the corners while Y atoms are at face centres What should be the formula of the compound if: one of the X atoms is missing from a corner in each unit cell.

A compound having empirical formula CH2Cl & its molar mass is 98.96. Find its molecular formula.

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

A compound Z is formed by the transfer of electrons form a metal X to a non-metal Y. Identify the type of bond formed in the compound. List three general properties of the compounds formed by such type of bonds.

In the spinel structur, oxides ions are cubical-closet packed whereas 1/8th of tetrahedral voids are occupied by A^(2+) cation and 1/2 of octahedral voids are occupied by B^(+) cations. The general formula of the compound having spinel structure is:

The existence of negatively charged particle in an atom was shown by J.J. Thomson as a result of the studies of the passage of electricity through gases at extremely low pressure known as discharge tube experiments. When a high voltage of the order of 10,000 volts or more was impressed across the electrodes, some sort of invisible rays moved from the negative electrode to the positive electrode these rays are called as cathode rays. Cathode rays travel in straight path in absence of electrical and magnetic field . Cathode rays consist of material part and charged particles? Cathode rays produce X-rays and light is emitted when they strike on ZnS screen. Cathode rays penetrate through thin sheets of aluminium and other metals . They affect the photogenic plate and passes heating effect when they strike on metal foil. The raito of charge to mass i.e charge/mass is same for all the cathode rays irrespective of the gas used in the tube. The existence of positively charged particle in an atom was shown be E. Goldstein. He repeated the same discharge tube experiments by using a perforated cathode. It was observed that when a high potential difference was applied between the electrodes, not only cathode rays were produced but also a new type of rays were produced simultaneoulsy from anode moving towards cathode and passes through the holes or canal of the cathode. These termed as canal rays or anode rays. These rays travel in straight lines and consists of positively charged particles. These rays have kinetic energy and produces heating effect also. The e/m ratio of these rays is smaller than that of electrons. Unlike cathode rays, their e/m value is dependent upon the nature of the gas taken in the tube. These rays produced flashes of light on ZnS screen and can pass throughs thin metal foils. They can produce physical and chemical changes and are capable to produce ionisation in gases. For cathode rays the value of e/m: