alleryStart learning →How are the exponents in a rate law obtained?
ABy experiment, watching rate change with concentration
BBy reading the coefficients in the balanced equation
CBy adding the charges of the reacting ions together
DBy counting the atoms present in each reactant
Answer & Solution
Correct answer: A. By experiment, watching rate change with concentration
1. The exponents in a rate law are the reaction orders.
2. They are found by changing one reactant concentration at a time and watching what happens to the rate.
3. That is an experimental measurement, not a calculation from the equation.
4. Reading the coefficients off the balanced equation only works for a single elementary step, and an overall equation is usually not elementary.
5. Charges and atom counts play no part in setting an order.
_Source: OpenStax Chemistry (CC BY 4.0), Ch 12 "Kinetics", section 12.3 Rate Laws_
Keep practising Kinetics
Browse all Kinetics questions for IMU CET, or explore more Chemistry topics.
Related questions
Which enzyme deficiency is described as the most common one in humans?Why are most catalytic converters preheated by an electric heater?Which catalyst coats the surface of most modern three way catalytic converters?Which international treaty began phasing out chemicals linked to ozone destruction?Which prize did Paul Crutzen, Mario Molina and Sherwood Rowland share for their work on ozNitric oxide takes part in the decomposition of ozone. Why is it called a catalyst?On a reaction diagram the reagents sit at 6 kJ and the transition state at 20 kJ. What is What effect does a catalyst have on the position of an equilibrium?