Oxygen

OC24 prepare a sample of oxygen by decomposing H₂O₂ using MnO₂ as a catalyst (word equation and chemical equation)

Hydrogen

Peroxide ▬▬▬▬▬▬▬▬▬▬► Water + Oxygen

H₂O₂ is broken down by the aid of a catylst

the flask the reaction occurs in is called a Buchner flask

Method

1. Set up apparatus as in the diagram. Ensure the seal on the buchner flask is tight, the water is above the beehive shelf
2. Add a small amount of Manganese Dioxide to the flask.
3. Allow some Hydrogen Peroxide into the flask. Write down your observations
4. Flood a Gas Jar with water, inverted (upside down) place the open end over the hole in the beehive shelf
5. Flood another jar in readiness for filling the 1st.
6. Discard this 1st Jar (mainly Air)
7. Continue to add more Hydrogen Peroxide

Gas Tests

Place a lit splint in to the gas jar. Write down your observations

The Splint Burns brightly

Place a glowing splint into the gas jar. Write down your observations

The Splint RELIGHTs

Pour some Limewater in the Jar. Write down your observations

There is no effect

Pour the contents onto a lit candle Write down your observations.

Nothing observed / candle burned brighter

Burn Magnesium, Write down your observations

Magnesium burns very brightly

Burn Magnesium in the Gas Jar Write down your observations.

Magnesium burns amazingly brightly

Pour some water into the spent gas jar and test with Litmus papers Write down your observations

Litmus paper turns Blue, indicating a base

The Characteristic Test for Oxygen is

that it will relight a glowing splint

Manganese Dioxide is a catalyst.

A Catalyst is something that changes the speed of a reaction.

Manganese Dioxide speeds up the rate at which Hydrogen Peroxide breaks down into Water and Oxygen.

It does not get used in the reaction

OC25 investigate the ability of oxygen to support combustion in a wooden splint and a candle, and state two uses of oxygen

There is enough oxygen in 2kg of moon dust to keep a human alive for a day!

When a wooden splint that is glowing, if it is placed in a test tube of oxygen it will burst into flames.

OC26 burn carbon and magnesium in oxygen, and test the products using moist litmus paper

Carbon is the basis for most fuels. Burning Methane gas is similar to burning Carbon, Candles too could be considered to be Carbon.

From this we see that CO₂ is given off by burning carbon in oxygen.

These gases when bubbled through water make the water acidic, this turns litmus paper red .

When Magnesium is burned in Oxygen, is burns very brightly.

Go here to list another element and its properties

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