Decomposition of Hydrogen Peroxide | Reactions | Chemistry | The Fuse School

in this lesson we will learn about how a

catalyst affects the rate of the

decomposition of hydrogen peroxide

fairly dilute solutions of hydrogen

peroxide approximately three to thirty

percent volume by volume can be used as

a household cleaning agent to remove

stains on furniture and clothing it can

also be used to bleach or lighten darker

hair whatever the real-life uses

hydrogen peroxide is always stored in a

dark plastic container away from

sunlight this is because in the presence

of warm conditions and UV light hydrogen

peroxide can decompose into water and

oxygen because the oxygen oxygen bond in

the molecule is unstable

since aqueous hydrogen peroxide and

water are clear and colorless liquids we

will monitor the rate of this reaction

by measuring the amount of oxygen

produced this decomposition reaction can

be catalyzed by manganese for oxide the

oxygen produced can be measured using a

gas syringe place a set amount of

hydrogen peroxide and add a small

spatula of manganese for oxide a fine

black powder quickly stopper the flask

so to prevent any evolved oxygen from

escaping into the surroundings you will

see that fizzing happens which shows

that oxygen gas is being produced this

is an exothermic reaction meaning that

heat energy is released the volume of

oxygen evolved can be recorded at

specific time intervals plotting the

volume of oxygen produced right against

time will give a graph that's similar to

this one right here we can measure the

rate of this reaction at any time in

this reaction by selecting a point on

the curve and drawing a line tangent to

the curve calculating the gradient of

the tangent will give you the rate of

the decomposition of hydrogen peroxide

that point in time a steeper gradient is

representative of a faster rate of

reaction whereas a less steep gradient

is representative of a slower rate of

reaction as you can see at the start of

the reaction the rate of decomposition

is very fast