differentiate between order and molecularity of a reaction???
Answers
DEFINITION: Order Sum of the exponents of the molar concentration(s) in the rate law expression. Molecularity The number of atoms, ions, molecules that must collide with one another simultaneously to result into a chemical reaction.
Order need not be a whole number. It can be fractional or zero. Molecularity is always a whole number.
Order can be determined experimentally only. Molecularity can be calculated by adding the no. of molecules in the slowest step (directly by looking at the balanced equation).
Order is applicable to simple + elementary reactions. Molecularity is applicable to simple reactions. No significance in determining molecularity of a complex reaction.
Order cannot be determined by looking at the stoichiometric coefficients. Molecularity can be determined by looking at the stoichiometric coefficients.
1). It is the sum of powers of Concentration terms in experimentally determined rate equation
2). it is experimental quantity
3). it can be 0,1,2... or even fraction
4). it is applicable to complex as well as alimentary reaction
MOLECULARITY:-
1). Number of reacting species taking part in alimentary reaction that must collide simultaneously to bring about a chemical equation
2). It is theoretical quantity
3). it cannot be zero or fraction
4). it is only applicable to alimentary reaction