Did you know that nitrogen is one of the most abundant elements on our planet? Nitrogen is essential for all life. So our reliance on nitrogen poses an interesting question. Is nitrogen flammable?
The answer may not be cut and dry. A few different scenarios can affect the fire risk concerning nitrogen. So let's look deeper into the truth behind the flame.
In this article, we'll discuss the reality behind nitrogen and fire, including what concentrations result in flammability and how to handle them safely.
Is Nitrogen Flammable?
No, nitrogen is not flammable. It does not burn or ignite when exposed to open flames or high temperatures. However, nitrogen can combine with other elements, such as oxygen, to form combustible and flammable compounds. Therefore, when used under certain conditions and with other flammable materials, nitrogen may present a fire hazard or produce an explosive mixture.
What Is Nitrogen?
It’s a good idea to learn a little about nitrogen itself before getting into its flammability. Nitrogen is a chemical element, one of the three essential elements that keep us alive, along with hydrogen and carbon.
Nitrogen makes up about 78.1% of our Earth’s atmosphere. At a standard temperature, the two nitrogen atoms form a triple bond, forming dinitrogen, also known as nitrogen gas.
Going into a little more detail, the nitrogen bond is a triple bond, which means it has the highest bond strength. Nitrogen gas is also colorless, odorless, tasteless, and non-toxic. Since the gas is lighter than air, you can use it in giant balloons to make them float.
Nitrogen’s melting point is -346°F (210°C), which is incredibly low, and its boiling point is -320.8°F (196°C).
Is Nitrogen Flammable Or Explosive?
Now that we understand some of the basics of nitrogen, let’s get into the conversation: how flammable is nitrogen? Nitrogen is not flammable, its triple bonds allow it to be significantly less reactive, and it doesn’t catch fire in most cases. So, given normal circumstances, nitrogen won’t ignite, nor is it considered combustible.
Well, is nitrogen explosive? Again, under normal circumstances, it’s not explosive; however, when placed in gas cans or other pressurized containers, it can become a hazard. If the can is heated, it causes the nitrogen molecules to expand and push against the can. This causes pressure and may lead the can to explode.
While nitrogen is not flammable or explosive in most cases, don’t treat it lightly. Keep nitrogen containers in a safe, isolated space away from people. You should also place the containers away from any heat source or fire. Better to be safe than sorry!
Can Nitrogen Catch Fire?
Nitrogen doesn't catch fire under normal circumstances, the same way it’s not flammable or explosive in normal conditions.
However, situations exist where nitrogen can catch fire, producing byproducts like nitrous oxide. The fact that nitrogen is a poor thermal conductor makes it non-reactive, so it doesn't catch fire under normal conditions.
This goes for the spontaneous combustion of nitrogen as well. It’s difficult enough for nitrogen to start burning under artificial conditions, so, given the circumstances, such as temperature and pressure being normal, there’s no fear of nitrogen just combusting by itself.
When discussing manufactured conditions, nitrogen can combine with some reactive metals, such as magnesium. In this scenario, the magnesium burns; however, the nitrogen supports the burning.
In some particular circumstances, nitrogen can react with hydrogen. The hydrogen burns and the nitrogen supports the burning process, making ammonia. It's essential to understand that it is an artificially manufactured process and doesn't happen naturally.
Thunderstorms are another rare condition under which nitrogen can combust. The lightning causes nitrogen to react with oxygen and creates nitric oxide. However, this only happens because lightning produces exceptional conditions, such as extremely high temperatures and pressure.
However, these are all artificially created or rare conditions under which nitrogen may be a threat or become explosive. In everyday, normal circumstances, the element is non-flammable and safe.
What Are Some Uses of Nitrogen?
Nitrogen is used for several processes and products. It makes ammonia, nitrates, nitric acid, and other industrial chemicals.
Nitrogen is also widely used in the pharmaceutical industry to manufacture antibiotics and kevlar. Light bulbs are another popular use case for nitrogen; since the gas is inert, light bulbs are filled with it to prevent oxidation and evaporation with the filament inside the bulbs.
Production of steel, aircraft fuel systems, pressurizing beer cans, and tire filling systems also involve using nitrogen.
However, as applicable as nitrogen is, its use can also pollute the environment. It is responsible for something called “eutrophication,” when too many nutrients are added to water, causing algae growth. It also causes other living organisms in the water to die. Most agricultural and industrial run-off water causes eutrophication.
What Is Liquid Nitrogen?
Liquid nitrogen is a liquid form of nitrogen made by cooling the gas to approximately -320°F (-196°C). It's colorless, odorless, and non-flammable, so it's safe to work with. Liquid nitrogen can also be used to freeze foods quickly.
Because of its low temperature and boiling point, liquid nitrogen remains a liquid at room temperature. When it evaporates, it quickly cools the atmosphere around it. This property makes liquid nitrogen useful for rapid freezing applications in industry and laboratories.
Liquid nitrogen is a beneficial chemical with dozens of unique applications in science, medicine, and industry. However, even though it is not flammable, you must handle it carefully as its cold temperatures can cause frostbite if exposed to the skin for too long.
Is Liquid Nitrogen Flammable?
As we’ve seen, nitrogen in its gas form does not tend to be flammable and is unreactive under normal circumstances. And in terms of flammability, liquid nitrogen is not flammable in the traditional sense either (it won't ignite when exposed to a spark or flame).
However, it does react with certain materials, such as combustible gases and liquids, which can lead to combustion or an explosion.
How Dangerous Is Liquid Nitrogen?
Liquid nitrogen is a dangerous substance. It is one of the cryogenic liquids and needs to be handled with extreme care. Safety considerations, such as wearing protective gear like goggles, clothing, and gloves, are essential when working with it.
Liquid nitrogen can cause horrific burns, blindness, airway inflammation, lung damage, heart problems, and even death if consumed. In addition, the liquid form is hazardous because it evaporates quickly, releasing large amounts of freezing nitrogen gas. Inhalation of this gas can cause the lungs to develop oxygen deprivation and cause asphyxiation or even fill the lungs with the cold liquid.
Furthermore, since the temperature of liquid nitrogen is so far below zero, any contact made with human skin will result in rapid, severe frostbite or even amputation if not properly contained or handled. So overall, it's essential to take every precaution necessary when handling this volatile element and seek professional advice if you plan to work with liquid nitrogen.
Can You Dispose Of Liquid Nitrogen In The Sink?
While it may seem like the obvious thing to do, you should never dump liquid nitrogen down the drain. The extremely low temperature of liquid nitrogen will cause significant damage to pipes and the sink itself.
If you want to dispose of liquid nitrogen, allow it to evaporate outdoors in a well-ventilated area. Ensure kids and pets are out of reach, even while it evaporates.
Why Is Nitrogen Not Used In Fire Extinguishers?
Nitrogen is not used in fire extinguishers because it does not have the chemical properties necessary to put out fires. It's an inert gas, so it doesn't easily form compounds or react with other chemicals. Additionally, while present in the air, it is lighter than carbon dioxide and oxygen, so it is not an effective blanket to smother the fire.
In contrast, most fire suppression systems use substances such as carbon dioxide, foam, or water. Carbon dioxide is heavier than air and blankets a flame while cutting off the oxygen source that fuels it. Foam disrupts a fire's chemical reaction by covering and cooling it. Water gets rid of heat energy (by cooling) but also smothers the flame by separating the combustible material and its oxygen source.
These three methods are more effective at putting out fires than nitrogen.
So, back to the initial question - is nitrogen flammable? After studying its properties and how it reacts, we can see that regular nitrogen is not flammable. The element forms powerful bonds, allowing it to be stable and not reactive under normal circumstances. At the same time, liquid nitrogen is a different story and can be dangerous.
The takeaway is that while regular nitrogen tends to be stable and nonflammable under normal conditions, you should still treat it cautiously and carefully. Remember, placing it in containers and exposing it to a heat source can cause it to become pressurized and explode.
Therefore, always store nitrogen and liquid nitrogen in a dry, well-ventilated area, away from heat and the reach of pets and children. If you want to dispose of liquid nitrogen, never pour it down the drain; instead, let it evaporate outdoors in a well-ventilated area.