Periodic Properties (I)
Diversity in the living world
Solid State (P)
Reproduction in organisms
U&D, Vector, Kinematics (11th)
Periodic Properties (I) , Atomic Structure (P) , Nomenclature (O)
Diversity in the living world, Reproduction in organisms
Mole fraction (x):
Average/Mean atomic mass:
Mean molar mass or molecular mass:
Calculation of individual oxidation number:
Formula: Oxidation Number=Number of electrons in the valence shell-number of electrons left after bonding
Concept of Equivalent weight/Mass:
For elements, equivalent weight (E) =
Where M=Molar mass
(v. f. = valency factor)
Concept of number of equivalents:
No. of equivalents of solute= No. of moles of solute × v.f
Normality=Molarity × v.f
Calculation of valency Factor:
n-factor of acid = basicity = no. of H+ ion(s) furnished per molecule of the acid.
n-factor of base = acidity = no. of OH-. ion(s) furnished by the base per molecule.
At equivalence point:
N1V1 = N2V2
n1M1V1 = n2M2V2
Volume strength of H2O2:
20V H2O2 means one litre of this sample of H2O2 on decomposition gives 20 lt. of O2 gas at S.T.P.
Measurement of Hardness:
Calculation of available chlorine from a sample of bleaching powder:
Where x= molarity of hypo solution and v=mL. of hypo solution used in titration.
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