3.15: Practical: Investigate the Effect of Changing the Surface Area of Marble Chips and of Changing the Concentration of Hydrochloric Acid on the Rate of Reaction between Marble Chips and Dilute Hydrochloric Acid

EFFECT OF SURFACE AREA AND CONCENTRATION ON THE RATE OF REACTION:

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EFFECT OF SURFACE AREA AND CONCENTRATION ON THE RATE OF REACTION

Diagram showing the Process of Downwards Displacement to Investigate the Effect of Surface Area and Concentration on the Rate of Reaction

CHANGING FACTORS: Surface Area: Add Different Sizes of Marble Chips ( Solid, Crushed and Powder ) Concentration: Add Different Concentrations of Hydrochloric Acid

METHOD: Add dilute Hydrochloric acid into a conical flask Use capillary tube to connect flask to a measuring cylinder placed upside down in a bucket of water (downwards displacement) Add Calcium Carbonate chips into conical flask and close the bung Measure the volume of gas produced in measuring cylinder in a fixed period of time Repeat with different sizes of Calcium Carbonate chips / concentration of Hydrochloric acid

RESULT:     Surface Area As the surface area of Calcium Carbonate increases, the rate of reaction will increase (positive correlation) This is because as the surface area to volume ratio of Calcium Carbonate chips increases, more surface area particles are exposed to the molecules of Hydrochloric acid, allowing more frequent successful collisions to occur - increase in rate of reaction This allows more frequent successful collisions to occur, increasing the rate of reaction     Concentration As the concentration of Hydrochloric acid increases, the rate of reaction will increase (positive correlation) This is because as the concentration of Hydrochloric acid increases, there will be more molecules of Hydrochloric acid present in given volume to react with surface area particles of Calcium Carbonate chips This allows more frequent successful collisions to occur, increasing the rate of reaction