reaction rates

• The rates of a chemical reaction are a measure of how fast a reaction occurs.
• The rate of a chemical reaction depends on the reaction that is taking place.
• Concentration is a measure of how many particles are in a solution.
• A high concentration has lots of particles, a low concentration has few particles.
• As the concentration increases, the rate of reaction increases.
• Increasing the concentration means that there are more particles.
• If there are more particles, there’s a greater chance of collisions taking place.
• As the temperature increases the rate of reaction increases.
• At higher temperatures molecules move faster, resulting in more collision per second and a faster reaction.
• Slow molecules are also less likely to lead to a reaction than fast ones.
• Decreasing the particle size means there is more area for the particles to react together and collide, increasing reaction rate.
• A catalyst is a substance which speeds up a reaction, remains chemically unchanged during the reaction and can be reused.
• The type and mass of the catalyst at the start of the reaction is the same at the end of the reaction.
• An enzyme is an example of a catalyst, it is a biological catalyst.
• the rate of a chemical reaction can be determined by measuring either:

   Changes in the concentration of reactants

  or products

   Changes in the mass of the reactants or

  products

   Changes in the volume of the reactants or

  products
• The rate of a chemical reaction is how fast the reactants are being used up and how fast the products are being made.
• the average rate of reaction can be calculated with the formula - average rate= ∆quantity divided by ∆time
• ∆quantity = change in quantity
• ∆time = change in time
• The steeper gradient of the reaction rate graph shows the faster the reaction reaction. The end point of each reaction can be clearly observed as when the curve flattens out.