If `N_(A)` is Avogadro's number, then the number of oxygen atom in one g-equivalent of oxygen is

If N_A is Avogadro's number, then the number of hydrogen atoms in one g-equivalent of hydrogen is :

Number of oxygen atoms in product x

The atomic number of oxygen is

Atoms and molecules are so small in size that it is neither possible to count them individually nor possible to determine their mass. These are counted collectively in terms of Avogadro's number. The mass of Avogadro's number of atoms and molecules is known as gram atomic mass and gram molecular mass respectively. The volume occupied by Avogadro's number of molecules of a gas or vapours is known as molar volume. If N_(A) is Avogadro's number, then the number of valence electrons in 4.2 g of nitride ions (N^(3-)) is :

Number of oxygen atoms in molybdate ion is

Number of oxygen atoms in molybdate ion is