A catalyst is a chemical molecule that is employed in small amounts to reduce the activation energy of a reaction and hence improve its rate. During a chemical reaction, the catalyst does not undergo any chemical modifications and stays in its initial condition throughout the process. Catalysts of many varieties, including zeolites, metals, chemical compounds, enzymes, and organometallic...
Russian 
English
French
Spanish
Portuguese
Deutsch
Turkish
Dutch
Italiano
Romaian
Portuguese (Brazil)
Greek
urdu