The aim of this note is to illustrate the approach initiated by the authors in[ 11 ] to model chemical reactions by edge relabeling chemical graph transformation rules, while describing an implementation on top of PerlMol[ 12 ]. 1 Partially supported by the Spanish DGES and the EU program FEDER, project BFM2003-00771 ALBIOM. 2 Partially supported by the Spanish CICYT, project MAVERISH (TIC2001-2476-C03-01) (more…)

Blending of chemical reactants is a common operation in the chemical process industries. Blend time predictions are usually based on empirical correlations. When a competitive side reaction is present, the final product distribution is often unknown until the reactor is built. The effects of the position of the feed stream on the reaction byproducts are usually unknown. Also, the scale up of chemical reactors (more…)

Stoichiometric chemical reactions have been classi- callyperceivedas systems of discrete reacting par- ticles wherein reactant species transform to product species. However, because the extreme number of particles involved, generally a significant fraction of Avogadro’snumber, the classical analytic model based on the Kinetic Mass Action Lawof Guldberg and Waageas expounded by Christianson (1964) treats (more…)

Chemical reaction stoichiometry (CRS) is a branch of chemical stoichiometry dealing with the constraints, in the form of chemical equations, placed on changes in the composition of a closed reacting system by the require- mentfor conservation of the amount of each atomic species and of the total charge. This simple conservation concept has far-reaching consequences for all of chemistry (more…)

A lliance UniChem, a pan-European wholesale distributor of pharmaceutical and healthcare products, is currently in the throes of developing a sales order system that it will deploy in its subsidiaries across Europe. Unusually, the company has opted for custom-built software because of the amount of tailoring it had to do to its previous ERP system. Alliance UniChem runs highly automated warehouses (more…)

The Field Chemistry is the central science. It is the science about substances, their composition, structure, properties, and interactions. Chemistry helps explain the physical world and its workings, and plays an important role in our lives. Chemists have contributed a great deal to technical advances of society and have made many important contributions to modern life. Everything is made from (more…)

Societal Image of Chemistry • Chemistry was once viewed as a field of innovation resulting in medical breakthroughs and modern convenience. • Chemistry is now viewed by many as fouling the planet. Zero Waste Alliance Historical Approach to Environmental Problems • Waste treatment, control, and disposal; pollutant monitoring; hazardous waste site cleanup. • Development of standards for (more…)

1. Moles and Masses The number of moles of a substance is defined as number of moles = mass RMM where the mass is in grammes (denoted by g) and RMM denotes the Relative Molecular Mass of the substance. Example 1 Calculate the number of moles of sodium chloride (NaCl) in 5.85 g given the Relative Atomic Mass data Na=23, Cl=35.5. Solution From the question, the RAMs for Na and Cl are, (more…)

Subject benchmark statements provide a means for the academic community to describe the nature and characteristics of programmes in a specific subject or subject area. They also represent general expectations about standards for the award of qualifications at a given level in terms of the attributes and capabilities that those possessing qualifications should have demonstrated. This subject benchmark statement, together (more…)

Abstract Chlorine atom spin-orbit product branching ratios and total absolute reaction cross sections have been measured for the H + DCl ? HD + Cl gas-phase reaction for collision energies of Ecol = 1.0, 1.4 and 1.7 eV. The measured Cl*(2P1/2) atom spin-orbit product branching ratios ?Cl*(1.0 eV) = [Cl*]/[Cl+Cl*] = (0.06 ± 0.02), ?Cl*(1.4 eV) = (0.07 ± 0.01), and ?Cl*(1.7 eV) = (0.16 ± 0.01) revealed the increasing importance of a non-adiabatic reaction (more…)