Why is catalyst used in powder form

This is another familiar lab reaction. Solid manganese IV oxide is often used as the catalyst. Oxygen is given off much faster if the catalyst is present as a powder than as the same mass of granules.

Catalytic converters use metals like platinum, palladium and rhodium to convert poisonous compounds in vehicle exhausts into less harmful things. For example, a reaction which removes both carbon monoxide and an oxide of nitrogen is:. Because the exhaust gases are only in contact with the catalyst for a very short time, the reactions have to be very fast.

The extremely expensive metals used as the catalyst are coated as a very thin layer onto a ceramic honeycomb structure to maximise the surface area. You are only going to get a reaction if the particles in the gas or liquid collide with the particles in the solid.

Increasing the surface area of the solid increases the chances of collision taking place. Imagine a reaction between magnesium metal and a dilute acid like hydrochloric acid. The reaction involves collision between magnesium atoms and hydrogen ions. A catalyst speeds up a reaction, an inhibitor slows it down. Catalysts do not change the equilibrium concentrations of reacting substances in reversible reactions.

However, they do reduce the time taken to reach equilibrium. Iron is a cheap catalyst used in the Haber process. It helps to achieve an acceptable yield in an acceptable time. Catalysts speed up a chemical reaction by lowering the amount of energy you need to get one going. Catalysis is the backbone of many industrial processes, which use chemical reactions to turn raw materials into useful products. Catalysts are integral in making plastics and many other manufactured items.

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