chemical kinetics

Half life of a reaction is defined as the time required for reducing the concentration of a reactant to half its initial value. It is denoted as t 1 / 2 . As discussed before, the t 1 / 2 of a zero order reaction is given as In general, for a reaction of order n, t 1 / 2 is proportional to initial ..

Rates of most chemical reactions increases with temperature because the rate constant 'k' increases with temperature. The temperature dependence of the rate constant is given by the Arrhenius equation, where..

Catalysis - It has been mentioned earlier that a catalyst usually increases the rate of reaction. A catalyst is not consumed in the reaction, it is used up in one step and then released in the next step. Catalytic reactions can be classified into two types. They are i) Homogenous reactions and ii) ..

Radioactive Dating - All radioactive decays follow first order kinetics. Therefore, the half-life of a radioactive element is independent of the amount of sample. With the help of half-life values of a suitable radioisotope of an element, which is present in a rock, or in an artefact, the..

Example 5: Cyclopropane (C 3 H 6 ) at room temperature has a ring structure. When it is heated, the ring opens up and cyclopropane isomerizes to propylene. The reaction takes place in a first order manner. Therefore, the rate law for the reaction is, rate (r) = k [C 3 H 6 ] 1 fig 6.5 - F..

First Order Reaction - Example 5: Cyclopropane (C 3 H 6 ) at room temperature has a ring structure. When it is heated, the ring opens up and cyclopropane isomerizes to propylene. The reaction takes place in a first order manner. Therefore, the rate law for the reaction is, rate (r) = k [C 3 H 6 ] 1..

Energy Barrier - In this theory, the rate constant is related to three factors Z, f and p by the equation k = Zfp b (19) where Z is the collision frequency f is the fraction of collisions having energy greater than the threshold energy and p is the fraction of the collisions that occurs with the re..

Example 7: Hydrogen (H 2 ) gas reacts with bromine (Br 2 ) gas to give hydrogen bromide vapor. The chemical reaction is represented by the equation as follow..

As noted earlier, the rate of reaction also depends on p, the fraction of collisions that occur with proper orientation. This factor is independent of temperature. Why proper orientation of the reactant molecule is important can be understood from the figure. fig 6.13 - Importance of molecular orie..

Orientation Barrier - As noted earlier, the rate of reaction also depends on p, the fraction of collisions that occur with proper orientation. This factor is independent of temperature. Why proper orientation of the reactant molecule is important can be understood from the figure. fig 6.13 - Import..