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Air for Breathing and Combustion

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Introduction

Air is a gas that is all around us and is necessary for both breathing and combustion. In this article, we will discuss the properties of air that make it so important for these two processes. Air is made up of different gases, including nitrogen, oxygen, and argon. These gases are necessary for both breathing and combustion because they each have unique properties that allow them to function in these processes. 


Nitrogen is the most common gas in air, making up about 78% of the total volume. It is a non-flammable gas that is inert, meaning it does not support combustion. Oxygen is the second most common gas in air, making up about 21% of the total volume. It is a flammable gas that is necessary for combustion. Argon is a non-flammable, inert gas that makes up about 1% of the total volume of air.


Inhaling and exhaling are both processes that allow us to get the oxygen we need from the air around us. Breathing is a vital process for people because it keeps us alive so we can continue to function. In this lesson, we will discuss how humans breathe and what role air plays in the process. When we breathe, the air enters our lungs, where it is diffused into our bloodstream. The oxygen in the air is then transported to all of the cells in our body, where it is used to produce energy. The carbon dioxide that is produced by our cells is then transported back to our lungs and exhaled. 


Air is necessary for breathing because it provides us with the oxygen we need to produce energy. Complex molecules called hydrocarbons are necessary for combustion. When a hydrocarbon is burned, it reacts with oxygen to produce carbon dioxide and water vapour. The carbon dioxide is then expelled from the body, and the water vapour is exhaled. Air is necessary for combustion because it provides us with the oxygen we need to react with the hydrocarbons.


The air around us is what is commonly known as the atmosphere of the Earth. The atmosphere is a huge blanket of air that envelopes the planet. It provides us with the air for respiration and shields us from the direct sun’s rays which can be damaging.  


The atmosphere consists of about 78% of nitrogen, 21% of oxygen, 0.93% of argon and 0.03% of carbon dioxide as well as other gases such as helium, ozone, argon and hydrogen in much lesser quantities.


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Why Is Air Necessary?

  • If the world had no atmosphere, it would be an extremely hostile, cold climate. The atmosphere and air around us help regulate and moderate the temperature of the Earth. 

  • Air is essential because it consists of the gases essential to sustain all life forms; humans, plants, animals and other organisms.

  • Air is crucial as it supports water to transition from one state to another through the process of the water cycle. The water cycle warrants that the planet doesn’t run out of water as it is a valuable resource and everyone receives it. Air replenishes lakes, rivers and other waterways to ensure everyone gets water.


Why Air is Vital for Respiration? 

The two main gases involved in the process of respiration are oxygen, and carbon dioxide. All the living organisms on Earth are able to live because of these two gases and all of us are dependent on them. The oxygen component is used by all living beings to react with glucose (a type of sugar that you get from food) to produce energy for different activities. This energy is used for growth, development and all other activities. Carbon dioxide and water are released as end products of respiration. Plants, on the other hand, breathe in carbon dioxide to convert the chemical energy using sunlight and release oxygen and glucose. This is the process in which they manufacture their own food, which is called ‘photosynthesis’. 


Why Is Air Necessary for Combustion?

Combustion is a high-temperature chemical process that releases a lot of energy which occurs between a fuel and an oxidant (oxygen-containing substance); mainly the oxygen present in the atmosphere. Combustion occurs at high temperatures and emits energy to the surroundings in the form of light and heat. This is why flames appear when combustion happens.


Methane is an important part of combustion; it combines with oxygen in the atmosphere and emits a coloured flame. The energy from the reaction can be utilised to heat things, cook food, produce electricity and also power vehicles.


Why is Air Vital for the Regulation of Temperature?

Air helps in the formation of winds. During summers, the land gets heated up much faster than the oceans; the temperature of the Earth’s surface rises rapidly. The air above the land is hot and thus rises, and the cold air from the sea surface moves and forms a layer above the land, thus not letting the temperature rise very high. This creates wind and helps regulate the temperature. The air and the atmosphere also form a protective layer around the planet and protect it from the excessive UV rays of the sun, thus, cooling the Earth down in the process.


Why Air is Needed for Burning? 

Combustion is very important since it helps not only to emit energy but also produce light as well. It is the primary source of energy and is essential to all life forms. 


To explain how and why air is important for burning, let us do an experiment i.e. the candle and glass experiment. For this experiment, you will require

  • One Candle

  • Candle Lighter or Matches (adult supervision is recommended)

  • A Glass jar or a drinking glass

  • Ceramic dinner plate or wooden board (optional)


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Method

  • Place the candle on the wooden board and light it using the candle lighter or matches. 

  • Watch the candle for a few moments and observe that it is burning simply and continuously, and the flame is not going off.

  • Now get the glass jar, it should be a transparent one, through which you can easily observe the candle and its flame.  

  • Place the glass jar upside down, so that the candle is inside the glass jar and covers it entirely. 


Result

  • You will see that the flame will get extinguished in a few seconds after keeping the glass jar.

  • This happens because when you keep the jar, the oxygen available inside the jar is limited, and thus when it is all used up, the flame will go off.

  • You can also observe small droplets of water along the inner surface of the glass jar. This shows that combustion releases water as a by-product. 


This experiment tells us that combustion is not possible without oxygen and that water is a by-product of the chemical reaction.


Conclusion

This is how air is important for different biological processes, burning, and regulation of temperature. Focus on the prime concept of the usage of air and learn what role is played by it in different processes. 

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FAQs on Air for Breathing and Combustion

1. What Do the Other Gases Present in the Air Do?

Nitrogen is more abundant in the atmosphere than oxygen. It is required by all living being; humans, animals, and plants for the production of proteins and other essential building units used as a source of energy. It is utilised for numerous commercial purposes. 


Uses of the oxygen we have already discussed; respiration, combustion and regulation of temperature. 


Argon is a colourless, odourless, and tasteless inert gas. It is utilised in gas-filled electric light bulbs, radio tubes and as an inert environment for arc-welding metals, such as aluminium and stainless steel; and for the production and of various metals, such as titanium, and uranium; and for developing semiconductor crystals, such as silicon and germanium.


Carbon dioxide is used by plants to manufacture and store their food, as discussed earlier. 

2. What is the Meaning of Air Pollution and its Effects?

Air pollution is the contamination of air by the addition of particles and gases. The addition of pollutants can have adverse effects which can vary from serious disease risks to the average temperature of the planet rising. Pollutants such as soot, smoke, pollen, methane, and carbon dioxide are deadly to the environment.


This pollution can occur through improper disposal of waste gases, deforestation, forest fires and soil erosion. 


The consequences are deadly ranging from respiratory diseases to nervous system damage and harm to liver, spleen and blood, and constant fatigue and headaches. 

3. What is oxygen?

Oxygen (O2) is a colourless and odourless gas that makes up about 21% of the atmosphere by volume. It is necessary for both breathing and combustion because it is the only gas that can be used to burn fuels. When a hydrocarbon is burned, it reacts with oxygen to produce carbon dioxide and water vapour. Oxygen is vital for our survival because it keeps us alive by allowing us to produce energy from the food we eat. Oxygen is a necessary part of the air because it is the only gas that can be used to burn fuels. When a hydrocarbon is burned, it reacts with oxygen to produce carbon dioxide and water vapour.

4. Where does Earth's oxygen come from?

The oxygen in Earth's atmosphere is a result of photosynthesis. Photosynthesis is the process that plants use to produce oxygen from carbon dioxide and water. Photosynthesis occurs when the sun's energy is used to convert carbon dioxide and water into glucose and oxygen. The plants use earth as a source of glucose for energy and release oxygen as a byproduct. Earth is a source of oxygen because plants use photosynthesis to create glucose and release oxygen as a byproduct. Photosynthesis is the process that plants use to produce oxygen from carbon dioxide and water.

5. What does carbon dioxide do for us?

Carbon dioxide is a colourless, odourless gas that makes up about 0.03% of the atmosphere by volume. It is produced when fuels are burned and is also a by-product of respiration. Carbon dioxide is necessary for both breathing and combustion because it is the only gas that can be used to extinguish fires. When a hydrocarbon is burned, it reacts with oxygen to produce carbon dioxide and water vapour. Carbon dioxide is vital for our survival because it helps us to breathe.


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6. Why is the air blue when we see it? 

When you look at the sky, you can see that the blue colour is dominant. This is because of the scattering of light by molecules of oxygen and nitrogen, which preferentially scatter short-wavelength light (blue), resulting in a blue sky. On the other hand, when you look at an object like grass, your eyes receive the reflected light (light that is not transmitted through the object) from the object. This light is received by the eye directly and does not go through the atmosphere, so there is no blue colour. This is why grass appears to be green since the reflected light from it is green.

7. What is the difference between breathing and respiration?

Breathing is a process that takes in the air into our lungs. Respiration is the process that takes place in the cells of our body, where the oxygen from the air is used to produce energy. The carbon dioxide from respiration is released through breathing. Breathing is a way to get oxygen into our blood, and respiration is the process of making use of it in the cells. With the help of breathing, carbon dioxide is eliminated. The air is necessary for both breathing and combustion because it provides us with the oxygen we need to produce energy and also with the nitrogen we need for breathing.