Chemistry – Chemical reactions - Rate of reaction | e-Consult
Chemical reactions - Rate of reaction (1 questions)
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Apparatus Required:
- Conical flask
- Delivery tube
- Inverted test tube filled with water
- Measuring cylinder (e.g., 50 cm3)
- Thermometer
- Hydrogen peroxide solution (e.g., 3% concentration)
- Catalyst (e.g., manganese dioxide – MnO2)
Method:
- Measure a known volume of hydrogen peroxide solution using a measuring cylinder and pour it into the conical flask.
- Add a small amount of manganese dioxide (MnO2) as a catalyst.
- Quickly connect the delivery tube to the conical flask and the inverted test tube filled with water. Ensure the test tube is completely filled with water.
- Start the reaction and measure the volume of oxygen gas produced over a specific time interval (e.g., 1 minute) using the volume of water displaced in the inverted test tube. Repeat the experiment several times.
- Vary the concentration of the hydrogen peroxide solution and repeat the experiment for each concentration.
Determining the Rate: The rate of reaction can be determined by calculating the volume of oxygen gas produced per unit time. This can be expressed as volume of O2 (cm3) / time (s). A graph of volume of O2 produced against time can be plotted. The slope of the graph will represent the rate of reaction. Alternatively, the rate can be calculated as the change in volume of O2 produced divided by the change in concentration of H2O2 over a specific time interval.