posted by Anonymous on .
1) The rate expression for the reaction 2 SO2 + O --> 2 SO3 is given by rate = k [SO2]2[O2]. The overall order of this reaction is: first order
2)The rate reaction between A and B is expressed as rate = k [A][B]. To produce the greatest increase in the reaction rate: double the [A]
3)A formula in brackets, for examples [NH3], indicates: the equilibrium concentration of ammonia
Are these true/false questions? If so, the answers are (1) T, (2) F, (3) F.
1. The reaction is second order with respect to SO2, first order with respect to O2, and third order overall.
2. Doubling A will be no more effective than doubling B so you know that can't be right. Changing BOTH A and B would be better. Better still, is changing temperature. Changing T by 10 degrees approximately doubles the rate of reaction.
3. You need to look in your text or notes to see how that is handled. Sometimes brackets mean concentration, sometimes activity.
I did not notice that what you wanted was for us to check your statement that followed the colon. The SO2 + O2 reaction (which you typed incorrectly as SO2 + O) is not first order, assuming the rate equation that you provided is correct. However, reactions of that type usually do not take place in a single three-reactant step. They require a series of steps that involve unstable chemically active free radicals, such as O.
In 2), remember that k is a constant only at a fixed temperature. In most cases, k increases rapidly with temperature, so that heating is the most effective way to achieve a higher reaction rate. At a fixed temperature, changing [A] or [B] by the same percent is equally effective.
In (3) a chemical compound expressed in brackets usually indicates its actual concentration, whether chemical equilibrium exists or not.