CO2 is the chemical symbol for carbon dioxide. This compound causes effervescence in sodas and many alcoholic beverages, elevation of bread, propulsion in some aerosols, and fire suppressing effect in fire extinguishers. The CO2 It can be produced deliberately or as a by-product of another chemical reaction.
Part 1 of 2: Make CO2 at home
Step 1. Get a 2-liter plastic bottle
Use plastic instead of glass, because if you can generate enough pressure to break the bottle, a plastic bottle will not explode the way a glass bottle would.
- If you plan to use the CO generator2 To supply carbon dioxide to the plants in your aquarium, a bottle of that size will provide an adequate supply for a 95 L (25 gal) tank.
Step 2. Add 2 cups (473 ml) of sugar
Use unrefined sugar instead of refined sugar, as this contains more complex sugars, which take longer for yeasts to break down. It is also cheaper.
Step 3. Fill the bottle, with warm water, to the place where it begins to curve towards the neck
Adding warm tap water is enough, but water that is too hot will kill the yeast.
Step 4. Add 1/2 teaspoon (2.5 ml) of baking soda
Baking soda is widely used in baking, and can be found in many stores.
Step 5. Add 1/2 teaspoon (2.5 ml) of yeast extract
If you can get it, this product will help the yeast last longer.
An example of a yeast extract is "Vegemite", which is very popular in Australia. Other yeast extracts include "Bovril", "Cenovis" and "Marmite"
Step 6. Add 1/3 teaspoon (1.6 ml) of yeast
Brewer's yeast lasts longer than bread yeast, but the latter lasts long enough for the reaction and is cheaper.
Step 7. Cap the bottle securely
Step 8. Shake the bottle to mix the yeast and sugar well
You should see a slight foaming on the surface of the water.
Step 9. Uncap the bottle
Step 10. Wait 2 to 12 hours
The water should begin to bubble during this time, which shows that the CO2 it is breaking free. If you don't see bubbling after 12 hours, you may have added too hot water, or the yeasts are not active.
The solution should bubble at approximately a rate of 2 bubbles per second. Bubbling faster could alter the pH of the water
Part 2 of 2: Other Ways to Produce CO2
Step 1. Exhale
Your body uses the oxygen that you inhale to react with the proteins, fatty acids, and carbohydrates that you eat. One of the results of this reaction is the carbon dioxide that you exhale.
In contrast, plants and some types of bacteria take carbon dioxide from the air and, using energy from the sun, make simple sugars (which are carbohydrates)
Step 2. Burn something that contains carbon
Life on earth is based on the element carbon. To burn something you need a spark, a source of fuel, and an atmosphere in which it can burn. The oxygen in our atmosphere reacts quickly with other substances, so when you burn something made of carbon you will get CO2.
- Calcium oxide (CaO), also known as “quicklime”, can be produced by burning limestone, which contains sodium carbonate (CaCO3). The CO2 it is expelled, leaving the calcium oxide (for this reason it is also known as "burnt lime").
Step 3. Mix chemicals that contain carbon
Carbon and oxygen, which form CO2, are found in various chemicals and minerals classified as carbonates or bicarbonates (if they also contain hydrogen). Reactions with other chemicals can release CO2 in air, or mix with water to form carbonic acid (H2CO3). Some of these reactions include:
- Hydrochloric acid and calcium carbonate. Hydrochloric acid (HCl) is the acid found in the human stomach. Calcium carbonate (CaCO3) is found in limestone, gypsum, eggshells, pearls, coral, and antacids. When the two substances mix, they form calcium chloride and carbonic acid, the latter decomposing into water and carbon dioxide.
- Vinegar and baking soda. Vinegar is a solution of acetic acid (C2H4OR2), while baking soda is made up of baking soda (NaHCO3). The mixture of these substances produces water, sodium acetate and CO2, in a reaction that usually foams.
- Methane and water vapor. This reaction is carried out industrially to extract hydrogen, by using steam at high temperatures. Methane (CH4) reacts with water vapor (H2O) to produce hydrogen (H2) and carbon monoxide (CO), which is a deadly gas. The carbon monoxide then mixes with water vapor, at lower temperatures, to produce more hydrogen and convert the deadly carbon monoxide into the safer carbon dioxide.
- Yeasts and sugar. When yeast are added to a sugary solution (as indicated in the instructions in part 1), they break down the sugar and produce CO.2. The reaction also produces ethanol (C2H5OH), the type of alcohol found in alcoholic beverages. This reaction is known as fermentation.
- To use, in your aquarium, the CO2 made in a bottle, you have to drill a small hole in its cap, put a rubber tube through it and stick it in that place. You should also have an air valve, both to prevent the water from being sucked in when the carbon dioxide escapes, and to release the pressure and prevent the bottle from exploding. Also, you can connect a bubble counter to see how fast the carbon dioxide is being released.
- Many times the CO2 it is produced in quantities too small to be caught. Unfortunately, when this carbon dioxide is released into the atmosphere in sufficient quantity, it traps the sun's heat and prevents it from returning to space, thus increasing the earth's temperature. Many scientists consider this fact to be the cause of climate change.