Gas-Solid Systems: Reactions Involving Several Gases When more than one reacting eases are involved in a chemical reaction, the overall rate will depend on the relative extent of adsorption of the different gases. If one…

Heterogeneous Reactions in Solution Heterogeneous reactions are also known in solutions. It is a solution composed of different states of matter. Examples: The reaction between acid and metal is a heterogeneous reaction. The decomposition of…

Autocatalysis: A single chemical reaction is said to have undergone autocatalysis, or be autocatalytic, if one of the reaction products is also a reactant and therefore a catalyst in the same or a coupled reaction.…

Gas – Solid Systems: Reactions Involving One Gas The following derivation, based on Langmuir’s theory of unimolecular adsorption layer, is made on the assumptions that- (i) the solid surface has a fixed number of adsorption…

Kinetics of Heterogeneous Reactions The chemical engineer regularly has to compare kinetic data for heterogeneous reactions merely and precisely in order to make practical predictions of reaction rates over a variety of conditions. The Langmuir-Hinshelwood…

Radiation Chemistry Chemical reactions brought about by the action of α, β, γ and X-rays, by rapidly moving electrons and by high voltage discharges are included in Radiation Chemistry. It is a subdivision of nuclear…

Photosynthesis Some very important reactions take place in nature by the action of light. One such reaction is the synthesis of macromolecules in the plant kingdom and is known as photosynthesis. It is a metabolic…

Photosensitized Reaction Photosensitization is a reaction to light that is mediated by a light-absorbing molecule, which is not the ultimate target. There are many substances that do not normally react when exposed to light. lf,…

Determination of Quantum Yield The fluorescence quantum yield is defined as the ratio of the number of photons emitted to the number of photons absorbed. Experimentally, relative fluorescence quantum yields can be determined by measuring…

The Laws of Photochemistry There are two basic laws of photochemistry. In 1817 Grotthus and later Draper stated that only that radiation which is absorbed by a substance is effective in producing a photochemical reaction.…