To monitor the rate of production of oxygen from hydrogen peroxide using manganese dioxide as a catalyst Flashcards
How can the reaction could be started at a known time?
Add catalyst, stopper and start clock
How is the gas produced collected?
Delivery tube is connected to gas collection system
How is the gas measured
Inverted graduated cylinder
Describe the appearance of the manganese dioxide before use
A black powdery solid
Name the products of the decomposition of hydrogen peroxide
Water and Oxygen
The hydrogen peroxide is said to be ‘20 volume’. What does this mean?
That a certain volume of hydrogen peroxide would give off 20 times that volume when it decomposes
What property of the gas allows collection under water?
The fact that oxygen is only sparingly soluble in water allows it to be collected under water
Describe the appearance of the manganese dioxide at the end of the reaction. Would you expect to see a change in appearance and explain
Black powdery solid
No, because the manganese dioxide acts as a catalyst and a catalyst is usually unchanged at the end of the reaction
Give one every day use of manganese dioxide
Manufacture of ‘dry’ batteries
Give a balanced equation for this reaction
H2O2 -> H2O + 1/2 O2
What type of catalysis was involved in these reactions?
Hetergenous
When the graph is plotted of the volume of gas produced versus time explain why the graph is steepest at the beginning
Highest concentration - more collisions
Calculate the total mass of gas produced in this experiment when its 78cm^3 volume
78 ÷ 24000 = 0.00325 mol × 32 = 0.104
