Gcse c6 rates of reactions revision
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This document discusses rates of reaction and enzymes. It explains that the rate of a chemical reaction depends on factors like temperature, concentration, surface area, and the presence of a catalyst. It then discusses how enzymes are biological catalysts that control reaction rates in the body, using yeast and fermentation as an example. Finally, it outlines some common uses of enzymes, such as in washing powders to digest stains and in baby food to pre-digest proteins.
Gcse c6 rates of reactions revision
- 1. C6 GCSE Revision Rates of Reaction 09/05/11
- 2. Rates of Reaction 09/05/11 Chemical reactions occur when different atoms or molecules collide: For the reaction to happen the particles must have a certain amount of energy – this is called the ACTIVATION ENERGY. The rate at which the reaction happens depends on four things: The temperature of the reactants, Their concentration Their surface area Whether or not a catalyst is used
- 3. Measuring rate of reaction 09/05/11 Two common ways: 1) Measure how fast the products are formed 2) Measure how fast the reactants are used up
- 4. Rate of reaction graph 09/05/11 Amount of product formed Time Slower reaction Fast rate of reaction here Slower rate of reaction here due to reactants being used up
- 5. Enzymes 09/05/11 Enzymes are biological catalysts. They help the reactions that occur in our bodies by controlling the rate of reaction. Yeast is an example of an enzyme. It is used to help a process called fermentation: The alcohol from this process is used in making drinks and the carbon dioxide can be used to make bread rise. Enzymes work best in certain conditions: Enzymes are denatured beyond 40 O C Sugar Alcohol + carbon dioxide Enzyme activity Temp pH pH 40 0 C Could be protease (found in the stomach) Could be amylase (found in the intestine)
- 6. Uses of enzymes 09/05/11 1) Enzymes are used in washing powders to help digest food stains. Biological washing powders will only work on 40 0 C or lower. 2) Enzymes are used in baby foods to “pre-digest” the proteins. 3) Enzymes are used to convert starch into sugar which can then be used in food. 4) Conversion of glucose into fructose – glucose and fructose are “isomers” (they have the same chemical formula), but fructose is sweeter. Daz