The catalyst may increase reaction rate or selectivity, or enable the reaction at lower temperatures.

Synthetic polymerization reactions may be carried out with or without a catalyst.

Crown ethers, like 15-crown-5, may be used as a phase-transfer catalyst.

For example, the methylation of benzene (), through a Friedel-Crafts reaction using as catalyst, may produce singly methylated, doubly methylated, or still more highly methylated products, as shown in the following example,

That first shot may have been accidental, or meant as a warning shot ; it was a catalyst for an exchange of gunfire.

Further, the most recent edition of Ives's biography admits that Anne may very well have had a personal spiritual awakening in her youth which spurred her on, not just as catalyst but expediter for Henry's Reformation, though the process took a number of years.

Some authorities have argued that this requires a strong governing authority to guide the work, and may have been a catalyst for the development of systems of governance in early civilizations.

Foss's presence, and his knowledge, ability, enthusiasm, and imagination may well have been the catalyst bringing hitherto unconnected activities together in Milford's mind, as another new venture similar to the establishment of the overseas branches.

A letter Wills wrote that year may have been a catalyst in the push to establish football teams with a " code of laws ".

Ralph is occasionally used as a catalyst for satire about public education's failings because of this, as he may be merely a victim of inflexible and incompetent teaching.

When a catalyst is used the reaction rate may be stated on a catalyst weight ( mol g < sup >− 1 </ sup > s < sup >− 1 </ sup >) or surface area ( mol m < sup >− 2 </ sup > s < sup >− 1 </ sup >) basis.

If the basis is a specific catalyst site that may be rigorously counted by a specified method, the rate is given in units of s < sup >− 1 </ sup > and is called a turnover frequency.

The battery compartment of a dive lamp may have a catalyst to recombine any hydrogen gas emitted from the battery, since gas cannot be vented in use.

If sulfur passes over a catalyst, it may be further oxidized in the catalyst, i. e., SO < sub > 2 </ sub > may be further oxidized to SO < sub > 3 </ sub >.

This work may have been the catalyst for the composition of the concerto.

However, while the arrival of Tate Modern in the London borough of Southwark may be heralded as a catalyst to economic revival in its surrounding neighborhood.

Ramona may not have been another Uncle Tom's Cabin, but it served, along with Jackson's writings on the Mission Indians of California, as a catalyst for other reformers .... Helen Hunt Jackson cared deeply for the Indians of California.

DHA may be prepared, along with glyceraldehyde, by the mild oxidation of glycerol, for example with hydrogen peroxide and a ferrous salt as catalyst.

Events in Hungary in 1956 may have stirred Shostakovich out of his compositional inertia and acted as a catalyst for his writing the symphony.

This can be potentially dangerous with persons who are already suffering from a form of identity disorder or may be a catalyst to instigate particular behaviors in a person who was previously believed to be of sound mental health.

Unlike other reagents that participate in the chemical reaction, a catalyst is not consumed by the reaction itself.

Unlike other reagents that participate in the chemical reaction, a catalyst is not consumed by the reaction itself ; however, it can be inhibited, deactivated or destroyed by secondary processes.

Other event-driven strategies include: credit arbitrage strategies, which focus on corporate fixed income securities ; an activist strategy, where the fund takes large positions in companies and uses the ownership to participate in the management ; a strategy based on predicting the final approval of new pharmaceutical drugs ; and legal catalyst strategy, which specializes in companies involved in major lawsuits.

Another important catalyst was another presbytery refusing to ordain a graduate of seminary, who, in good conscience, declared that he would refuse to participate in the ordination of a woman, although he affirmed that he would willingly serve in a pastorate with ordained women on the staff.

Global Internship is an outstanding catalyst to explore culture, participate in a variety of real life ministries, and find out how you personally fit into God ’ s plan for the world.

Potowomut, located on the Narragansett Bay, consists of multiple residential neighborhoods resulting in a catalyst of sewage over-spill into Narragansett Bay.

Power Packaging has a long history of managing multiple customer facilities and dedicated facilities within the industry and has proven to be a diverse and innovative growth catalyst to the packaging industry.

In present time, Batman requires his blood to create a cure for a disease that Batman, Joker, and multiple people of Gotham City are afflicted with, as the cure would degrade too quickly without the unique chemical formula of the Lazarus Pit and Ra's ' prolonged exposure to it having turned his blood into an organic catalyst that would prevent degradation.

SO < sub > 2 </ sub >- rich gases enter the catalytic converter, usually a tower with multiple catalyst beds, and are converted to SO < sub > 3 </ sub >, achieving the first stage of conversion.

Haskell's paper was obtained by the pro-life movement within weeks, and served as a catalyst for Congressional hearings, federal legislation, multiple lawsuits, and more than thirty state bills prohibiting " partial-birth abortion ".

Catalysis is the change in rate of a chemical reaction due to the participation of a substance called a catalyst.

Generic potential energy diagram showing the effect of a catalyst in a hypothetical exothermic chemical reaction X + Y to give Z.

With the rapid recovery in automotive and chemical industry overall, the global catalyst market is expected to experience fast growth in the next years.

Schematic potential energy diagram showing the effect of a catalyst in an endothermic chemical reaction.

Therefore, in order to define the quantity of a catalyst, the rate of conversion of a defined chemical reaction has to be specified, preferably of the first order, under strictly controlled conditions.

Lutetium usually occurs in association with the element yttrium and is sometimes used in metal alloys and as a catalyst in various chemical reactions.

As a compound, nickel has a number of niche chemical manufacturing uses, such as a catalyst for hydrogenation.

Any chemical species that is regenerated, such as a catalyst, also has a stoichiometric coefficient of zero.

Water is widely used in chemical reactions as a solvent or reactant and less commonly as a solute or catalyst.

In 1857, French microbiologist Louis Pasteur proved in the paper " Mémoire sur la fermentation alcoolique " that alcoholic fermentation was conducted by living yeasts and not by a chemical catalyst.

Without a chiral influence ( for example a chiral catalyst, solvent or starting material ), a chemical reaction that makes a chiral product will always yield a racemate.

Hardeners in these systems are commonly called catalysts, but since they do not re-appear unchanged at the end of the reaction, they do not fit the strictest chemical definition of a catalyst.

For platinum two d-bands cross the Fermi level, changing its chemical behaviour ; it is used as a catalyst.

* Homogeneous catalysis, a sequence of chemical reactions that involve a catalyst in the same phase as the reactants

* Diphenylamine, a chemical stabiliser used in homogeneous propellants to absorb the catalyst produced by the autocatalytic decomposition of propellants

Hydrogenation-to treat with hydrogen-is a chemical reaction between molecular hydrogen ( H < sub > 2 </ sub >) and another compound or element, usually in the presence of a catalyst.

A single chemical reaction is said to have undergone autocatalysis, or be autocatalytic, if the reaction product itself is the catalyst for that reaction.

The graph for these equations is a sigmoid curve, which is typical for autocatalytic reactions: these chemical reactions proceed slowly at the start because there is little catalyst present, the rate of reaction increases progressively as the reaction proceeds as the amount of catalyst increases and then it again slows down as the reactant concentration decreases.

This lighter worked by passing flammable hydrogen gas, produced within the lighter by a chemical reaction, over a platinum metal catalyst which in turn caused it to ignite and give off a great amount of heat and light.

Generic potential energy diagram showing the effect of a catalyst in a hypothetical endothermic chemical reaction.

A catalyst is a substance that accelerates the rate of a chemical reaction but remains chemically unchanged afterwards.