Title BRDC CHE 06 CRISS CROSS RAD(07 Apr 2016).ppt ✅

CHEMISTRY
Let us learn about … Various radicals, writing the formula of a substance using criss - cross method
(Acids, bases & salts) Writing the formula of a compound Inorganic compounds Positively charged radical (or) Electro positive radical (or) Basic radical (or) Cation Negatively charged radical (or) Electro negative radical (or) Acidic radical (or) anion Ex : NaCl ⇒ Na+Cl- NH4Cl ⇒ NH4+ Cl-
The total ‘+ve’ charge on basic radical is equal to the total ‘-ve’ charge or acid radical in a molecule. ∴ In writing the formula, the +ve & -ve radicals must be taken in the inverse ratio of their valencies. (criss – cross method) Example : BaSO4 +2 -2 Writing the formula of a compound