Basic Concepts of Chemistry Flashcards
What is Law of conservation of mass
Matter is neither created nor destroyed during a physical or chemical change. Mass of reactants before reaction = mass of products after reaction
What is law of definite proportion
A pure chemical compounds always consists of the same elements combining in a fixed ratio by weight
What is law of multiple proportion
When two elements combine to form two or more products, the weight of one element which combines with the fixed weight of another bears a whole number ratio
What is law of reciprocal
When two elements combine with the same weight of C separately, the ratio in which they do so is the same or a whole number ratio in which they directly combine.
What is molecular mass
The average relative mass of a molecule compared to a C12 atom taken as 12 on the a.m.u scale
What is Avagadro’s number (defination)
It is the number of particles present in one mole of any substance
What is Avagadro’s number (number) in atoms and litres
6.023 x 10^23
22.4L at S.T.P
What is one mole of a substance?
One mole is the amount of substance which contains the same amount of particles as as there are atoms in 12g of C12
What is equivalent weight
It is the number of parts by weight which combines with 1.008 parts by weight of hydrogen or 8 parts by weight of oxygen
What is formula of equivalent weight of acid
molecular weight of acid/ basicity
What is the relation between atomic weight and equivalent weight
atomic weight = equivalent weight x valency
What is the equivalent weight of a base
molecular weight/ acidity
What is the formula for mass percentage
(mass of solute / 100 g of solution) * 100
What is volume percentage
(mass of solute/100mL of solution)*100
What is normality
It is the number of gram equivalents of solute dissolved per litre of solution
