Final answer:
A catalyst is a substance that increases the rate of a chemical reaction without itself undergoing any change. Using a catalyst in high concentration can further increase the rate of the reaction. This is because a higher concentration of the catalyst provides more opportunities for collisions with the reactant molecules, increasing the chances of successful reactions.
Step-by-step explanation:
In chemistry, a catalyst is a substance that increases the rate of a chemical reaction without itself undergoing any change. Catalysts work by lowering the activation energy required for the reaction to occur, which allows the reaction to happen more quickly. When a catalyst is used in high concentration, it means that a large amount of the catalyst is present relative to the reactants.
Using a catalyst in high concentration can often further increase the rate of the reaction. This is because a higher concentration of the catalyst provides more opportunities for collisions with the reactant molecules, increasing the chances of successful reactions. Additionally, a higher concentration of the catalyst can help to sustain a faster reaction rate over a longer period of time.
For example, in the production of ammonia, a catalyst is used at high concentrations to accelerate the reaction rate at relatively moderate temperatures. This allows for a more efficient production process.