To calculate the number of atoms of Cr, we first find the number of moles per unit of cubic centimeter of Cr. Then, use avogadros number for the number of atoms. Calculations are as follows:
1 cm^3 (7.15 g/cm^3) (1 mol / 51.996 g Cr) = 0.14 mol Cr
0.14 mol Cr ( 6.022 x 10^23 atoms Cr / 1 mol Cr ) = 8.28 x 10^22 atoms Cr
KCI is not a covalent compound, it is an ionic compound.
A covalent compound is one in which each of the atoms involved contribute a specific number of electrons for sharing in order to from stable compound while an ionic compound is a compound formed when one atom donates electron to the other atom in the compound, in order to attain stability. The compounds given in options A, B and D shared electrons while in KCl, potassium donates an electron to chlorine.
Explanation:
10 valence electron are there