How Does Temperature Affect the Rate of Reaction?

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On a hot, summer day, if you consider yourself to be a chemistry experiment, you will perspire more quickly than on a cooler day. This is the reaction rate of your body when you are outside in warmer temperatures. The same holds true for turning up the heat on a chemical reaction.

How and Why Does Temperature Affect the Rate Constant for a Reaction?

When you increase the temperature of any system, it increases the average kinetic energy of each of the components. As the kinetic energy increases, it causes the components to move faster and collide into each other more frequently in a given amount of time. This results in the components having a greater energy or force on each collision. The increase in activity and energy increases the reaction rate to arrive at the end product more quickly.

On the other hand, if you reduce the temperature, most reaction rates will also decrease.

How Does Temperature Affect the Rate of Diffusion?

The process of diffusion is a passive process represented by particles spreading from areas of high concentration to areas of low concentration until the particles are evenly distributed through a space or container. The rate of diffusion is how quickly this process takes place.

When you apply heat, the atoms vibrate more quickly and collide more often to increase the rate of diffusion. For example, if you have water in a glass and add something colored to it, such as blue food coloring, you can see the two mixing together slowly until the entire glass turns into a lighter blue. If you use very warm water and add blue food coloring, the two will diffuse or mix together more rapidly.

How Does Temperature Affect the Rate of Respiration in Yeast?

Yeast is the ingredient in bread that makes it rise and become lighter. Yeast ferments sugar and releases carbon dioxide as a waste product. When temperatures are warmer, yeast will react and ferment more quickly. The rise in temperature increases the metabolic rate of activity in yeast, which you can see by placing warm water in a test tube, adding yeast to it and measuring the pressure in the test tube. If the yeast would respire aerobically in the air, there would be no change in pressure, as the oxygen would be consumed at the same rate as carbon dioxide is produced.

How Does Temperature Affect the Rate of Reaction of an Enzyme?

An enzyme is a macromolecular biological catalyst that accelerates chemical reactions to change the components into a product. When you raise the temperature of an enzyme, the process accelerates quickly. Increasing the temperature by ten degrees Centigrade will increase most enzyme activity by anywhere from 50 to 100 percent. Even raising the temperature by 1 or 2 degrees Centigrade can produce an increase in the chemical reaction by 10 to 20 percent.


About the Author

Mary Lougee has been writing about chemistry, biology, algebra, geometry, trigonometry and calculus for more than 12 years. She gained the knowledge in these fields by taking accelerated classes throughout college while gaining her degree.