Carbon monoxide and carbon dioxide

Introduction

Imagine being in a city throbbing with activity, as there are so many cars, factories, and buildings on both sides. While to us these are symptoms of development, each factor is a known contributor to air quality, central to environmental and human health improvement. Two main contributors to air pollution are carbon monoxide, CO, and carbon dioxide, CO₂, both compounds of carbon. These gases are ubiquitous in urban environments and hold huge, potential impacts on global warming, climate change, and human health. The present paper has focused mainly on the understanding of carbon compounds their nature, properties, different areas, and their applications or consequences in real life. By the end of this paper, you will have a long rundown of CO and CO₂: what they can do about climate and why they are important to daily life and scientific studies.

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This Story also Contains

1. Diversity of Elements of Carbon Monoxide and Carbon Dioxide
2. Relevance and Applications in Real Life Relating to Academics
3. Recommended Video:

Carbon Monoxide and Carbon Dioxide Explained

Carbon monoxide is an odorless and colorless gas that results from incomplete combustion of all carbon-based materials. It is highly poisonous because it binds with blood hemoglobin in the circulatory system and thus blocks the transport of oxygen. Low levels of CO may come with headaches, dizziness, and fatigue; higher concentrations are lethal.

The second is carbon dioxide, a colorless gas with a faint, sharp odor and a somewhat acidic taste. This gas is emitted in the combustion of every carbon-containing substance and is an end product of respiration in animals and plants, or during fermentation. Not toxic at normal atmospheric levels, high CO₂ concentrations can cause breathing difficulties, while more importantly, it acts like one of the greenhouse gases that brings about global warming.

Direct oxidation of C in a limited supply of oxygen or air yields carbon monoxide.

$2 \mathrm{C}(\mathrm{s})+\mathrm{O}_2(\mathrm{~g}) \xrightarrow{\Delta} 2 \mathrm{CO}(\mathrm{g})$

On a small scale, pure CO is prepared by dehydration of formic acid with concentrated H₂SO₄ at 373 K.

$\mathrm{HCOOH} \xrightarrow[\text { conc. } \mathrm{H}_2 \mathrm{SO}_4]{373 \mathrm{~K}} \mathrm{H}_2 \mathrm{O}+\mathrm{CO}$

On a commercial scale, it is prepared by the passage of steam over hot coke. The mixture of CO and H₂ thus produced is known as water gas or synthesis gas.

$\mathrm{C}(\mathrm{s})+\mathrm{H}_2 \mathrm{O}(\mathrm{g}) \xrightarrow{473-1273 \mathrm{~K}} \mathrm{CO}(\mathrm{g})+\mathrm{H}_2(\mathrm{~g})$

When air is used instead of steam, a mixture of CO and N₂ is produced, which is called producer gas.

$2 \mathrm{C}(\mathrm{s})+\mathrm{O}_2(\mathrm{~g})+4 \mathrm{~N}_2(\mathrm{~g}) \xrightarrow{1273 \mathrm{~K}} 2 \mathrm{CO}(\mathrm{g})+4 \mathrm{~N}_2(\mathrm{~g})$

Water-gas and producer gas are very important industrial fuels. Carbon monoxide in water gas or producer gas can undergo further combustion forming carbon dioxide with the liberation of heat. Carbon monoxide is a colorless, odorless, and almost water-insoluble gas. It is a powerful reducing agent and reduces almost all metal oxides other than those of alkali and alkaline earth metals, aluminum, and a few transition metals. This property of CO is used in the extraction of many metals from their oxide ores.

In CO molecule, there are one sigma and two π bonds between carbon and oxygen, :C ≡ O:. Because of the presence of a lone pair on carbon, CO molecule acts as a donor and reacts with certain metals when heated to form metal carbonyls. The highly poisonous nature of CO arises because of its ability to form a complex with hemoglobin, which is about 300 times more stable than the oxygen-hemoglobin complex. This prevents hemoglobin in the red blood corpuscles from carrying oxygen around the body and ultimately results in death.

Diversity of Elements of Carbon Monoxide and Carbon Dioxide

In several processes, CO and CO₂ belong to different areas with their peculiar properties and functions. Carbon monoxide has a strong connection it has with air pollution and health effects. There exist a variety of sources that generate carbon monoxide together with emissions from motor vehicles, industrial processes, and residential heating systems. This creates a need for monitoring and control of CO, hence becoming important parameters in securing public health and safety.

It is prepared by the complete combustion of carbon and carbon-containing fuels in excess of air.

$\begin{aligned} & \mathrm{C}(\mathrm{s})+\mathrm{O}_2(\mathrm{~g}) \xrightarrow{\Delta} \mathrm{CO}_2(\mathrm{~g}) \\ & \mathrm{CH}_4(\mathrm{~g})+2 \mathrm{O}_2(\mathrm{~g}) \xrightarrow{\Delta} \mathrm{CO}_2(\mathrm{~g})+2 \mathrm{H}_2 \mathrm{O}(\mathrm{g})\end{aligned}$

In the laboratory, it is conveniently prepared by the action of dilute HCl on calcium carbonate.

$\mathrm{CaCO}_3(\mathrm{~s})+2 \mathrm{HCl}(\mathrm{aq}) \rightarrow \mathrm{CaCl}_2(\mathrm{aq})+\mathrm{CO}_2(\mathrm{~g})+\mathrm{H}_2 \mathrm{O}(\mathrm{l})$

On a commercial scale, it is obtained by heating limestone.
It is a colorless and odorless gas. Its low solubility in water makes it of immense biochemical and geo-chemical importance. With water, it forms carbonic acid, H₂CO₃ which is a weak dibasic acid and dissociates in two steps:

$\begin{aligned} & \mathrm{H}_2 \mathrm{CO}_3(\mathrm{aq})+\mathrm{H}_2 \mathrm{O}(\mathrm{l}) \rightleftharpoons \mathrm{HCO}_3^{-}(\mathrm{aq})+\mathrm{H}_3 \mathrm{O}^{+}(\mathrm{aq}) \\ & \mathrm{HCO}_3^{-}(\mathrm{aq})+\mathrm{H}_2 \mathrm{O}(\mathrm{l}) \rightleftharpoons \mathrm{CO}_3^{2-}(\mathrm{aq})+\mathrm{H}_3 \mathrm{O}^{+}(\mathrm{aq})\end{aligned}$
H₂CO₃/HCO₃^– buffer system helps to maintain the pH of blood between 7.26 to 7.42. Being acidic in nature, it combines with alkalies to form metal carbonates.
Carbon dioxide, which is normally present to the extent of ~ 0.03 % by volume in the atmosphere, is removed from it by the process known as photosynthesis. It is the process by which green plants convert atmospheric CO₂ into carbohydrates such as glucose. By this process, plants make food for themselves as well as for animals and human beings. Unlike CO, it is not poisonous. However, the increase in combustion of fossil fuels and decomposition of limestone for cement manufacture in recent years seem to increase the CO₂ content of the atmosphere. This may lead to an increase in the greenhouse effect and thus, raise the temperature of the atmosphere which might have serious consequences.
Carbon dioxide can be obtained as a solid in the form of dry ice by allowing the liquified CO₂ to expand rapidly. Dry ice is used as a refrigerant for ice cream and frozen food. Gaseous CO₂ is extensively used to carbonate soft drinks. Being heavy and non-supporter of combustion it is used as a fire extinguisher. A substantial amount of CO₂ is used to manufacture urea.

Although carbon dioxide is non-toxic in small amounts, it is vital for the earth's carbon cycle. It is one of the greenhouse gases responsible for trapping heat in the atmosphere due to global climate change. Anthropogenic activities producing CO₂ include the burning of fossil fuels, deforestation, and several industrial procedures. Mitigation measures for CO₂ come in the form of renewable energy, carbon capture technologies, and reforestation.

Relevance and Applications in Real Life Relating to Academics

Proper understanding of CO and CO₂ is very important relative to mitigating environmental problems and to human health. Carbon monoxide detectors are essential safety gadgets installed in homes and building structures that warn occupants of potentially dangerous levels of the gas CO. It should effectively carry out intense public awareness about the dangers caused by CO poisoning, particularly during winter when heating systems continuously run.

In climate science, carbon dioxide is the principal component in global warming and climatic change research. It, therefore, forms core international agreements under the Paris Agreement aimed at containing an increase in global temperature. This makes studying CO₂ relate to disciplines such as chemistry, environmental science, and engineering. Research looks into new means of capture and storage for carbon, alternative sources of energy, and sustainable practices that bring down the impacts of CO₂.

Solved Examples :

Example 1: Water gas is:

1)Water vapour

2)CO + H₂O

3) (correct)CO + H₂

4)CO + N₂

Solution

As we learn

Water gas is a mixture of CO and H₂. It is produced when steam is passed over hot coke

$\mathrm{C}+\mathrm{H}_2 \mathrm{O}(\mathrm{g}) \xrightarrow{473-1273 \mathrm{~K}} \mathrm{CO}+\mathrm{H}_2$

Hence, the answer is the option (3).

Example 2 : When air is passed over hot coke it produces:

1)Water gas

2) (correct)Producer gas

3) Syngas

4)Coal gas

Solution

As we learn

Producer Gas is a mixture of CO and N_{2 .} It is produced when air is passed over hot coke

$2 \mathrm{C}+\mathrm{O}_2+4 \mathrm{~N}_2 \xrightarrow{1273 \mathrm{~K}} 2 \mathrm{CO}+4 \mathrm{~N}_2$

Hence, the answer is the option (2).

Example 3: Which of the following is correct?

1) $\mathrm{Fe}+3 \mathrm{CO}_2 \rightarrow \mathrm{Fe}_2 \mathrm{O}_3+3 \mathrm{CO}$
2) $\left(\right.$ correct) $\mathrm{ZnO}+\mathrm{CO} \rightarrow \mathrm{Zn}+\mathrm{CO}_2$
3) $\mathrm{Mg}+\mathrm{CO} \rightarrow \mathrm{MgO}+\mathrm{C}$
4)None of these

Solution

As we have learned,

CO is used as a reducing agent in the extraction of metals from their oxides. It is able to reduce elements that have a medium to low reactivity. e.g., Zn, Fe, Sn, etc

$\begin{aligned} & \mathrm{Fe}_2 \mathrm{O}_3+3 \mathrm{CO} \xrightarrow{\Delta} 2 \mathrm{Fe}+3 \mathrm{CO}_2 \\ & \mathrm{ZnO}+\mathrm{CO} \xrightarrow{\Delta} \mathrm{Zn}+\mathrm{CO}_2\end{aligned}$

It is not able to reduce metals with greater reactivity, such as K, Na, Mg, Al, etc.

Hence, the answer is the option (2).

Recommended Video:

Summary

Carbon monoxide and carbon dioxide are two very important compounds of carbon. CO is a poisonous by-product that might lead to serious health hazards if proper combustion does not take place. Monitoring and control of the contents should be done making CO₂ one of the potent greenhouse gases that is central in the issue of climate change, in which the world enforces more control on its emission. Dealing with CO−Co² challenges brought about by these gases may pave our way toward a healthy and sustainable future.