How to make hydrogen ( explosive Gas ), storing hydrogen and some of the things that you can do with it. Floating trash bag, exploding trash bag, burning bubbles, exploding egg shell, exploding pringles, exploding milk jug carton, hydrogen stove and last but not least burning hydrogen bubbles in my hand.
In this article I am going to show you how to make and store hydrogen gas using easily obtainable materials.
To make the hydrogen we can use aluminium, sodium hydroxide and water.
The hydrogen is created in a flask by combining the sodium hydroxide, aluminium and water.
This creates an exothermic reaction which heats up the water rapidly. Along with the hydrogen we also have water vapour which can carry traces of the sodium hydroxide. To remove as much of this as possible we pass the gas through cold water using a device called a bubbler, which in this case is a soda bottle filled with water.
During use the bubbler also helps to prevent any flames passing back down the pipework and potentially exploding the flask.
To store the hydrogen we are going to make a system that displaces water from a lower bottle into a higher bottle. The gas is pressurised by the weight of the water and can be released by a tap when required. The storage system gives a visual indication of how much gas has been dispensed which can make some experiments safer.
In the video I also show some of the experiments that you can perform with the hydrogen gas, for example burning bubbles, floating a trash (rubbish) bag, exploding a trash bag, exploding an egg, Pringles can rocket, exploding a milk carton and burning some hydrogen bubbles in my hand.
Gas generation parts required
- 6mm or 1/4 inch pipe
- One large 1.7 or 2 litre soda bottle
- 500ml (or greater) Erlenmeyer glass heatproof flask
- Rubber stopper with hole to fit the flask
- Glass soda straw to fit the hole in the rubber stopper
- Epoxy adhesive
- Sandpaper
- Drill
- Step drill
- Hacksaw
Make the gas generation system
- Cut two lengths of tube 30cm / 1ft and 60cm / 2ft
- Sand the top of the soda bottle
- Drill two holes through the soda bottle top
- Enlarge the holes with a step drill until the pipes just fit through.
- The 60cm / 2ft pipe should pass through the cap and just reach the bottom of the soda bottle
- The 30cm / 1ft pipe should pass through the cap by approx 10mm
- Glue the pipes in place using epoxy adhesive
- Push the glass soda straw through the rubber stopper hole
- Heat the end of the 60cm / 2ft pipe to make it more flexible
- Push the end of the 60cm / 2ft pipe over the glass soda straw
- The rubber stopper fits into the neck of the Erlenmeyer flask
Gas storage parts required
- Two large 1.7 or 2 litre soda bottles
- 6mm or ¼” pipe
- Non return or check valve
- 6mm or ¼” aquarium tap
- Hard plastic party straws
- Epoxy adhesive
- Sandpaper
- Drill
- Step drill
- Hacksaw
Prepare the gas storage bottle top
- Cut two 5cm or 2″ lengths of the party straw
- Cut one 3cm or 1″ length of the party straw
- Sand the 1st soda bottle lid inside and out
- Drill three holes through the lid
- Enlarge the holes with a step drill until the straws can just fit through
- Sand the bottom of the shorter straw
- Sand the middle of the two longer straws
- Fit the straws through the lid
- Glue the straws in place inside and outside using epoxy adhesive
Prepare the expansion bottle base
- Cut a 5cm or 2 inch section of straw
- Sand the base of the second soda bottle
- Drill a hole through the base of the second soda bottle
- Enlarge the hole with a step drill until the straw just fits through
- Sand the base of the straw
- Fit the straw into the hole in the base of the second soda bottle
- Using epoxy adhesive glue the straw into place
Prepare the expansion bottle top
- Cut a 5cm or 2 inch section of straw
- Sand the 2nd soda bottle lid inside and out
- Drill a hole through the lid
- Enlarge the hole with a step drill until the straw can just fit through
- Fit the straw into the hole
- Using epoxy adhesive glue the straw into place
Gas storage pipework assembly
- Cut a length of pipe (approx 33cm or 13″) to reach the bottom of the gas storage bottle (1st soda bottle)
- Heat the end of the pipe to make it flexible
- Fit the pipe to one of the two longer straws inside the gas storage bottle top (1st soda bottle)
- Cut a 30cm or 12″ length of pipe
- Push one end on to the aquarium tap
- Push the other end on to the outside of the short straw of the gas storage bottle (1st soda bottle)
- Cut a 1m or 40″ length of pipe
- Push it on to the other end of the aquarium tap
- Cut a 40cm or 16inch length of pipe
- Push it on to the outside of the second long straw on the gas storage bottle top (1st soda bottle)
- Push the other end of the pipe on to the non return check valve (output end)
- Cut a 20cm or 8inch length of tube
- Push it on to the outside of the first long straw (This is the straw that has a pipe connected to the inside)
- Push the other end of the tube on to the base of the gas expansion bottle (2nd soda bottle)
Mount the gas storage and expansion bottles
To mount the bottles wrap some steel wire around the neck of each soda bottle to form a hook and attach the soda bottles to a length of wood using screw eyes.
Connect the gas generation to gas storage
Push the output pipe from the gas generation bubbler on to the non return check valve
(input).
Setup the bubbler and gas storage
- Fill the bubbler with water until it’s three quarters full
- Fill the bottom gas collection bottle until it is almost full
- Screw on all of the lids tightly
Safety
Sodium hydroxide is extremely corrosive and can cause you serious harm so please wear protective gloves, clothes and eyewear.
Hydrogen is highly flammable and when mixed with oxygen becomes explosive, so some care is necessary when you use it. Protective clothing, face shield and ear protectors are a sensible precaution.
Also be careful to expel any air in the tubes when you first use the gas. The first batch of hydrogen is often explosive because it is mixed with this air.
Making hydrogen gas
You are going to need:
- 20g sodium hydroxide
- Aluminium foil
- Distilled water
- 40 litre trash bag
- Add the distilled water into the heatproof flask.
- Slowly add the sodium hydroxide until it is dissolved
- Add the balls of aluminium foil
- Replace the rubber stopper
Avoid getting the rubber stopper or the neck of the flask wet, otherwise it can be difficult to keep the stopper in place.
The reaction starts slowly at first with a small but steady stream of hydrogen passing through the bubbler and into the storage bottle. As production increases the hydrogen displaces water from the storage bottle into the bottle above it.
Once the storage bottle is full, the excess hydrogen bubbles up through the top expansion bottle and can be collected by securing a trash bag over the top with an elastic band.
Burning hydrogen bubbles
Note that the first time you do this you will get bubbles containing hydrogen mixed with air from the pipes. The bubbles will explode rather than burn.
- Add some soapy water into a container
- Put the pipe from the gas storage bottle into the container
- Open the gas tap
You should now have some hydrogen bubbles that you can ignite with a barbeque lighter.
Exploding an egg
- Drill a small 2mm hole in the top of an egg
- Drill a larger 4mm hole in the base of the egg
- Blow out the contents of the egg into a bowl
- Wash and dry the egg
- Place some tape over the hole in the top
- Push a juice carton straw into the end of the gas pipe
- Push the straw into the bottom hole in the egg
- Turn on the gas tap and fill the egg with hydrogen
- Move the straw around in the egg to help expel air
- Turn off the gas tap and remove the straw from the egg
- Place the egg on a holder
- Remove the tape from the top of the egg
- Using a barbeque lighter quickly light the top hole of the egg
You should hear a pop when the hydrogen ignites. It’s very difficult to see the flame burning and it may take one or two minutes for the egg to explode, usually just when you think it’s not going to work!
The flame at the top of the egg burns the hydrogen which is lighter than air, air is drawn up into the bottom hole and when enough oxygen is present the mixture becomes explosive and the egg pops.
Exploding an Easter egg with hydrogen
Floating trash bag
Once the trash bag has inflated you can release it and tie the bottom. A 40 litre trash bag has a fair amount of lift, more than a helium filled balloon.
Fine fishing line is light enough to allow the bag to float to a considerable height.
Exploding trash bag
You can explode a tethered hydrogen trash bag by lighting it with a candle or taper tied to the end of a 10ft garden cane. The shock wave from this is quite surprising.