Search results
Results from the WOW.Com Content Network
In chemical thermodynamics, the reaction quotient (Q r or just Q) [1] is a dimensionless quantity that provides a measurement of the relative amounts of products and reactants present in a reaction mixture for a reaction with well-defined overall stoichiometry at a particular point in time.
A and B are reactant chemical species, S and T are product species, and α, β, σ, and τ are the stoichiometric coefficients of the respective reactants and products: α A + β B ⇌ σ S + τ T. The equilibrium concentration position of a reaction is said to lie "far to the right" if, at equilibrium, nearly all the reactants are consumed.
Reactants and products are formed at such a rate that the concentration of neither changes. It is a particular example of a system in a steady state . In physics , concerning thermodynamics , a closed system is in thermodynamic equilibrium when reactions occur at such rates that the composition of the mixture does not change with time.
Stoichiometry is used to run calculations about chemical reactions, for example, the stoichiometric mole ratio between reactants and products. The stoichiometry of a chemical reaction is based on chemical formulas and equations that provide the quantitative relation between the number of moles of various products and reactants, including yields ...
The pressure dependence of the equilibrium constant is usually weak in the range of pressures normally encountered in industry, and therefore, it is usually neglected in practice. This is true for condensed reactant/products (i.e., when reactants and products are solids or liquid) as well as gaseous ones.
A complete mechanism must also explain the reason for the reactants and catalyst used, the stereochemistry observed in reactants and products, all products formed and the amount of each. S N 2 reaction mechanism. Note the negatively charged transition state in brackets in which the central carbon atom in question shows five bonds, an unstable ...
PhET Interactive Simulations is part of the University of Colorado Boulder which is a member of the Association of American Universities. [10] The team changes over time and has about 16 members consisting of professors, post-doctoral students, researchers, education specialists, software engineers (sometimes contractors), educators, and administrative assistants. [11]
For a given reaction, porous supports must be selected such that reactants and products can enter and exit the material. Often, substances are intentionally added to the reaction feed or on the catalyst to influence catalytic activity, selectivity, and/or stability. These compounds are called promoters.