Question

The order of a reaction can be determined from:

• A. Heat change
• B. Stoichiometry
• C. Experimental data
• D. Ellingham diagram

Hint:

Don't confuse reaction order with stoichiometric coefficients—they are often different. Always use experimental data to determine the correct order.

Answer 1

The Correct Option is C

The order of a reaction refers to the power to which the concentration of a reactant is raised in the rate law expression.
It cannot be determined from heat changes, stoichiometry, or diagrams like Ellingham. Instead, it must be deduced from experimental data—typically by measuring how the rate of reaction changes with varying concentrations of reactants.
For example, using the method of initial rates, one can compare how changing the concentration of a particular reactant affects the reaction rate and thereby determine the order with respect to that reactant.
Therefore, only experimental data can reveal the actual kinetics and reaction order.