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The sub-shell that comes after f-sub-shell is called g-sub-shell. The number of g-sub orbitals in g-sub-shell and the total number of orbitals in the principal orbital respectively are;

The rate law of the reaction
product is given by
. If A is taken in large excess, the order of the reaction will be

The decay constant of a radioactive element is 0.0693 . The time required to reduce the activity of the sample to 1/8 of its initial activity will be;

Several techniques have been developed to determine the order of reaction. The rate of reaction cannot be predicted on the basis of the overall equation, but it can be predicted on the basis of the rate-determining step. For instance, the following reaction can be broken down into three steps.

In this case, the first step in the reaction pathway is the rate-determining step. Therefore, the overall rate of the reaction must equal the rate of the first step, where k is the rate constant. (Rate constants of the different steps are denoted by , where X is the step number).

In some cases, it is desirable to measure the rate of a reaction in relation to only one species. In a second- order reaction, for instance, a large excess of one species is included in the reaction vessel. Since a relatively small amount of this large concentration is reacted, we assume that the concentration essentially remains unchanged. Such a reaction is called a pseudo first-order reaction. A new rate constant, , is established, equal to the product of the rate constant of the original reaction, k, and the concentration of the species in excess. This approach is often used to analyze enzyme activity.

In some cases, the reaction rate may be dependent on the concontration of a short-lived intermediate. This can happen if the rate-determining step is not the first step. In this case, the concentration of the intermediate must be derived from the equilibrium constant of the preceding step. For redox reactions, the reaction rate at equilibrium can be correlated with the voltage produced by two half- cells by means of the Nernst equation. For the redox reaction taking place in the cell as: , the cell otential at any moment is given by

In a test of the Step-3 of Reaction-1, a solution is prepared containing a 0.1 M concentration of E and a 50 M concentration of C. The rate is calculate after the reaction has gone 50% to completion. By what percent will the calculated rate differ from the true rate if we treat the reaction as pseudo first- order?

Which of the following is true of a reaction at equilibrium?

Catalysts are effective in increasing the rate of a reaction because they;