How Do Catalysts Speed Up Reactions? L.O: To understand how catalysts affect the rate of a reaction

Oxygen can be produced by the chemical reaction Hydrogen peroxide  Water + Oxygen How could you make this reaction happen quickly to supply low hospitals? Remember it needs to be cheap on the NHS and safe!!

Catalysts For chemical reactions to occur: Existing bonds have to begin breaking so that new ones can be formed. Existing bonds have to begin breaking so that new ones can be formed. The molecules have to collide in such a way that the reacting parts of the molecules are brought together. The molecules have to collide in such a way that the reacting parts of the molecules are brought together. Catalysts can help with either or both of these processes. A catalyst is a substance that speeds up a reaction without getting used up in the process. Catalysts never produce more product – they just produce the same amount more quickly.

Other catalysts, especially enzymes, absorb molecules in a way that not only stretches bonds but also brings the reacting parts of reactants right next to each other. Catalysts

H H H H H H H H H H H H Bond stretched The stretching of the H-H bond lowers the activation energy and helps hydrogen react with the oil Ni catalyst Catalysts In the presence of a nickel catalyst vegetable oil and hydrogen react to form margarine.In the presence of a nickel catalyst vegetable oil and hydrogen react to form margarine. Nickel adsorbs hydrogen gas onto its surface in such a way that the bond holding the hydrogen molecule together becomes stretched.Nickel adsorbs hydrogen gas onto its surface in such a way that the bond holding the hydrogen molecule together becomes stretched. This partial breaking of the bond lowers the activation energy making hydrogen more reactive.This partial breaking of the bond lowers the activation energy making hydrogen more reactive.

Hydrogen Peroxide (H 2 O 2 ) Is a pale blue liquid slightly more viscous than waterIs a pale blue liquid slightly more viscous than water It is found in disinfectant, bleachesIt is found in disinfectant, bleaches In virtually all living organisms there are peroxidases (enzymes) which decompose hydrogen peroxide into oxygen and water.In virtually all living organisms there are peroxidases (enzymes) which decompose hydrogen peroxide into oxygen and water. Hydrogen peroxide is very oxidising so can loose its extra oxygen.Hydrogen peroxide is very oxidising so can loose its extra oxygen.

Your task is to find the best catalyst to break down hydrogen peroxide and produce oxygen quickly for hospitals You will be investigating catalysts manganese dioxide, lead oxide, iron oxide and liver.You will be investigating catalysts manganese dioxide, lead oxide, iron oxide and liver. They will vary in effectivenessThey will vary in effectiveness You will need to measure the oxygen production every 10 secs for up to 2 mins to find out which is the best catalyst at speeding the rate of reaction.You will need to measure the oxygen production every 10 secs for up to 2 mins to find out which is the best catalyst at speeding the rate of reaction. Design your experiment using the equipment provided. Draw your own results table to record the results.

Catalysts are used in the manufacture or application of a huge number of products. Synthetic materials like polyester are made using a catalyst. Manufacture of fertiliser via the Haber Process involves use of an iron catalyst. Plastics are made using catalysts. Biological soap powder uses biological catalysts (enzymes) Enzymes in pineapple help cooked ham to be more tender. Catalysts Catalytic Converters in cars – converting nitrous oxide and carbon monoxide to carbon dioxide and nitrogen

Catalytic converters in cars Catalytic converters have a high surface area to increase the rate of reaction. They also work best at high temperatures. A catalytic converter is a device that is fitted to the exhaust pipe of a car to clean up exhaust fumes. The converter uses platinum as a catalyst. It catalyzes the conversion of carbon monoxide and nitrogen oxide into the less polluting carbon dioxide and nitrogen.

Brita Filters use catalysts A Brita filter removes unwanted ions like chlorine, copper and lead. Inside the filter a chemical reaction occurs quickly on a carbon catalyst to remove carbon

Make a table of the advantages and disadvantages of using brita filters or catalytic converters. AdvantagesDisadvantages

Catalysts in industry Products can be made more quickly, saving time and money. Catalysts reduce the need for high temperatures because less energy is required for reactions. This saves fuel and reduces pollution.