Carbon Dioxide Vs Carbon Monoxide


Carbon is considered to be the element that is present in almost all objects that we use in our day-to-day life and also is the basic element for the formation of almost all biological and abiological beings present on our planet Earth. Its elements are spread all over and are widely used to make life easier and to operate the basic and complex processes of life. From the making of medicines to the manufacturing of soft drinks, from the materials used in constructing decorative materials to that of huge infrastructures, carbon, and its compounds are used everywhere and contain great importance. This article is all about carbon dioxide vs carbon monoxide.

As we know there are three basic states of matter found, which are solid, liquid, and gas. Carbon too has its compounds in various states. In the solid state, carbon constitutes elements like diamond, Graphite, fullerenes, etc. Liquids like ethanol, acetone, acetic acid, formic acid, some ethers, etc. are all made up of carbon.

When we talk about the gaseous state of the carbon element, we find various gases present in the atmosphere which are made up of carbon. There are many gases as well which are made in laboratories for some special purposes. Gases of carbon are made by the carbon atom forming bonds with other atoms of various elements. Atoms that form bond includes oxygen, sulfur, nitrogen, etc.

This article would discuss two such gases present in the atmosphere. The gases are Carbon dioxide and Carbon monoxide. The article will tell us about the structure, formation, uses, effect, properties, and differences between the two gases. As we know every coin has two sides, objects which provide benefits to us may have adverse effects as well and can harm us in some or the other way. Hence we should be aware of the demerits of elements that are being in use.


Carbon Dioxide

Carbon dioxide is an odorless and colorless gas that constitutes of two atoms of oxygen, bonded with a single atom of carbon. The symbolic representation of Carbon dioxide is CO2.

Carbon dioxide is a gas that is formed naturally in the environment. There are certain methods, processes, and reactions which result in the formation of CO2. Hence, carbon dioxide is a gas that is created by both natural process and synthetic processes.

As we all are familiar that, almost all animals including humans exhibit carbon dioxide through respiration. Plants are the entities that inhale carbon dioxide, as it is an ingredient for photosynthesis. In return, they exhale oxygen into the atmosphere.

In normal atmospheric conditions, CO2 is considered to be harmless. But excessive emission of carbon dioxide leads to an increase in the greenhouse effect. The greenhouse effect is the process in which the heat gets trapped in the Earth’s atmosphere, this helps to regulate the temperature of the planet and make a suitable environment for the growth of plants, animals, and other organisms.

This is done by using certain gases, which are known as Greenhouse Gases. These gases consist of carbon dioxide, methane, nitrous oxide, and water vapor. Due to the excess emission of these gases, the Earth’s temperature is increasing rapidly which leads to Global warming.

Carbon Monoxide

Carbon Monoxide is a colorless, odorless, and tasteless gas made of carbon. The structure of Carbon monoxide consists of a single oxygen atom bonded with a single carbon atom. Its structure is symbolically represented as CO.

Unlike CO2, carbon monoxide is a toxic gas. When a human or any other animal inhales CO, the gas causes serious health risks to the organism.

It is formed by incomplete combustion processes. The incomplete combustion process takes place when there is insufficient oxygen. Places or contexts where incomplete combustion can take place include combustion engines, wooden stoves, industrial processes, etc.

Mixes with the blood and disrupts the general functioning of the hemoglobin. Hemoglobin is present in the red blood cells which are responsible for the transportation of oxygen in the body.

Carbon monoxide when inhaled, gets into the blood and then forms a bond with hemoglobin resulting in the formation of carboxyhemoglobin. This compound reduces the ability of blood to carry oxygen, causing the deficiency of oxygen in tissues and organs.


Carbon Dioxide

Carbon dioxide compound consists of various properties, which helps us to define its physical state or physical properties as well as it chemical reactivity and properties which when known to us defines the behavior of the compound when it is being treated with various reagents and other chemical substances. The properties are:

1. Physical State

Carbon dioxide is a gas that does not possess any significant taste and hence is considered to be tasteless. Also, it is being observed that when carbon dioxide is under STP conditions that is standard temperature and pressure, it is an odorless and colorless gas. But when kept under low temperatures it is present in solid as well as liquid state.

2. Density

In normal atmospheric conditions, Carbon dioxide tends to settle nearer to the ground, which makes it circulate in an area closer to the Earth’s surface. This happens because the density of carbon dioxide is greater than that of air.

3. Solubility

Carbon dioxide is soluble in water. When dissolved in water, it forms carbonic acid (H2CO3). The solubility of CO2 in water increases with decreasing temperature and increasing pressure.

4. Chemical Reactivity

Carbon dioxide is a compound that generally shows inert behavior with respect to chemical reactions, this is because carbon dioxide is stable at standard conditions. But, it is found that carbon dioxide reacts with some specific substances under specified conditions.

For example, CO2 can combine with water to form carbonic acid, which can further dissociate into bicarbonate ions (HCO3-) and hydrogen ions (H+).

5. Acidic Properties

The compound shows acidic behavior even when it is dissolved with other substances, making it acidic in nature. When CO2 is dissolved in compounds like water(H2O) it decreases the pH of the solvent and increases its acidity.

6. Greenhouse Gas

As mentioned earlier in the article, the gas has the property to trap heat and thus helps in the trapping of heat causing the Greenhouse effect. This also regulates climate change to some extent.

Carbon Monoxide

The gas made up of carbon, carries various properties, let us now discuss them one by one and also have a look at how these properties affect the reactivity of the gas as well the environment.

1. Color and Odor

Like carbon dioxide, Carbon monoxide is also an odorless and colorless gas. The gas does not have a smell or such property, that makes it difficult to identify the gas in normal conditions and without any proper instrumentation.

2. Toxicity

Carbon monoxide is highly toxic to humans and animals. When inhaled, it binds to hemoglobin in red blood cells, reducing their ability to carry oxygen to vital organs and tissues. Prolonged exposure to high levels of carbon monoxide can lead to carbon monoxide poisoning, which can be life-threatening.

3. Combustible

It is a byproduct of the combustion process, the gas is inflammable and can also be used as a fuel when oxygen is present along with it, hence executing the combustion process.

4. Lower Density than Air

Unlike carbon dioxide, this gas tends to move upwards and rises farther from the Earth’s surface. This behavior proves that the gas is less dense than Air.

5. Chemical Reactivity

Carbon monoxide shows inert behavior when conducting any chemical reactions with other elements, this is due to the stability of the gas. The carbon atom is completely bonded with the oxygen, breaking the possibilities of reacting with any other compound or element. But under some conditions and with specific reactants carbon monoxide shows some chemical reactivity.


Carbon dioxide

Carbon dioxide (CO2) finds applications in various fields due to its unique properties. Here are some notable applications of carbon dioxide:

1. Food and Beverage Industry

Commonly used to create a sparkling effect. Also used for the preservation and storage of foods, increasing their shelf life.

2. Fire Suppression Systems

Due to its non-combustible properties, it is used in fire extinguishers, the gas displaces oxygen and stops combustion.

3. Welding

Carbon dioxide combined with inert gases like argon provides an inert environment for welding. If during the welding process if other gases like oxygen enter the welding region they may oxidize the workpiece and may change the properties of it.

4. Oil and Gas Industry

Carbon dioxide is employed in the oil and gas industry for enhanced oil recovery (EOR). Injecting CO2 into oil wells helps to extract additional oil that would otherwise be difficult to recover. Additionally, carbon dioxide can be used for natural gas purification and processing.

5. Chemical and Pharmaceutical Processes

Carbon dioxide is a versatile chemical compound used in various chemical and pharmaceutical processes. It can be utilized as a solvent, a pH regulator, and a reactant for producing chemicals, such as urea, salicylic acid, and sodium bicarbonate. In pharmaceutical applications, CO2 is used for extracting plant compounds, creating foaming agents, and as a sterilization agent.

6. Metal Fabrication

Due to the inert nature of the gas, the metals acquire a protective environment around their surfaces.

Carbon monoxide

Carbon monoxide (CO) has some industrial applications, although they are relatively limited due to its toxic nature. Here are a few notable applications of carbon monoxide.

1. Chemical Synthesis

Carbon monoxide acts as a primary ingredient for the manufacturing of various compounds. The compounds formed by carbon monoxide are also used in making plastic products, solvents, and some pharmaceutical products.

2. Metal Carbonyls

Carbon monoxide when reacted with any transition metal, forms metal carbonyls. These metal carbonyls have various industrial uses. These are used in the precursors for metal deposition in electronics and thin film production.

3. Chemical Reducing Agent

It acts as a strong reducing agent and can be employed in certain chemical reduction reactions. It can be used to convert metal oxides into their corresponding metals in industrial processes.

4. Fuel Gas

As mentioned earlier as well the gas in the presence of oxygen can be used as a fuel.

Since the gas possesses toxic nature as well, there is limited usage of it and during these processes, one must take precautions and should handle the compound carefully.

Difference between Carbon dioxide and Carbon monoxide

Carbon dioxide

Carbon Monoxide

The compound consists of one Carbon atom bonded with two oxygens. The compound consists of one carbon atom bonded with one oxygen.
In the gaseous form, it is denser than air. The gas is less dense than air.
It is not directly toxic in nature. It is strongly toxic and also can cause serious health issues.
Relatively more stable, and non-reactive. Has lesser stability, and can react with other compounds.
Non-combustible in nature. Can be used as a fuel when combined with oxygen.
Used for extinguishing fire. Used as a fuel for combustion.
At -78.5 degree Celsius, it turns solid. The gas becomes solid at -192.3 degree Celsius.
Can be used in Foods and beverages for sparkling and smoking effects. Not generally used due to its toxic nature.


1. What’s the difference between carbon dioxide and carbon monoxide?

Carbon dioxide is a carbon compound made formed by the bonding of one Carbon atom with two atoms of oxygen, whereas Carbon monoxide is formed by the bond formation of one Carbon atom with one Oxygen atom.

2. Is carbon monoxide heavier than carbon dioxide?

No, Carbon monoxide is lighter than Carbon dioxide as carbon dioxide has 2 oxygen atoms, whereas carbon monoxide has only one atom of oxygen. It is also less dense than carbon dioxide.

3. what’s worse CO2 or carbon monoxide?

Carbon monoxide is much worse than carbon dioxide as the gas is highly toxic in nature.

Written By: Bharat Awasthi