What is it called when fuels burn in oxygen to release energy?
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To move an airplane or a
model rocket through the air, we must use a propulsion system to generate thrust. Different types of aircraft use different types of propulsion devices, but all aircraft rely on some type of engine to generate power.
Rocket engines, internal combustion, or piston engines, and jet engines all depend on the burning of fuel to produce power. Burning a fuel is called combustion, a chemical process that we study in middle or high school. Because combustion is so important for aircraft and rocket propulsion, we will review the
fundamentals. Combustion is a chemical process in which a substance reacts rapidly with oxygen and gives off heat. The original substance is called the fuel, and the source of oxygen is called the oxidizer. The fuel can be a solid, liquid, or gas, although for airplane propulsion the fuel is usually a liquid. The oxidizer, likewise, could be a solid, liquid, or gas, but is usually a gas
(air) for airplanes. For model rockets, a solid fuel and oxidizer is used. During combustion, new chemical substances are created from the fuel and the oxidizer. These substances are called exhaust. Most of the exhaust comes from chemical combinations of the fuel and oxygen. When a hydrogen-carbon-based fuel (like gasoline) burns, the exhaust includes water (hydrogen + oxygen) and carbon dioxide
(carbon + oxygen). But the exhaust can also include chemical combinations from the oxidizer alone. If the gasoline is burned in air, which contains 21% oxygen and 78% nitrogen, the exhaust can also include nitrous oxides (NOX, nitrogen + oxygen). The temperature of the exhaust is high because of the
heat that is transferred to the exhaust during combustion. Because of the high temperatures, exhaust usually occurs as a gas, but there can be liquid or solid exhaust products as well. Soot, for example, is a form of solid exhaust that occurs in some combustion processes. During the combustion process, as the fuel and oxidizer are turned into exhaust products, heat is generated. Interestingly, some
source of heat is also necessary to start combustion. Gasoline and air are both present in your automobile fuel tank; but combustion does not occur because there is no source of heat. Since heat is both required to start combustion and is itself a product of combustion, we can see why combustion takes place very rapidly. Also, once combustion gets started, we don't have to provide the heat source because the heat of combustion will keep things going. We don't have to keep lighting a
campfire, it just keep burning. To summarize, for combustion to occur three things must be present: a fuel to be burned, a source of oxygen, and a source of heat. As a result of combustion, exhausts are created and heat is released. You can control or stop the combustion process by controlling the amount of the fuel available, the amount of oxygen available, or the source of heat. Navigation ..
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What do petrol, natural gas, wood and coal have in common? They are all fuels, which means that they can be burned to release energy. VideoWatch the video below to find out what happens during a reaction. While you are watching, think about the meanings of combustion, fuel and oxidation. What is a combustion reaction? Katie: Dr. Tim Gregory knows a thing or two about creating things that go BANG and BOOM. So, given today's subject is all about chemical reactions, we couldn't be in better company. We're looking at combustion and oxidation in relation to chemical reactions. I mean, it sounds really exciting, sir. But, what do we actually need to to get started? Dr. Tim: It is really exciting. This is one of my favourite subjects. So, combustion is a chemical reaction when a fuel is burned to release energy. A fuel is a substance which is burned to release energy in a useful way. And the final thing we need to know is oxidation. This is when a substance gains an oxygen atom in a reaction and this happens during combustion. Katie: Um, excited. This really does sound like fun. Can you give us an example? Dr. Tim: There are loads of examples of combustion, but I think it's best we explore this for now on a piece of paper. I'm going to show you the fire triangle. And this shows the three things that we need for a fire to start. The first thing we've got is a fuel and this is what we'd burn to release useful energy. The second thing we've got is oxygen and in the case of a fire we get the oxygen from the air. And the third thing that we need is to start a fire - we need a heat source. These are the three things that we need to start a fire. And if just one of the sides is taken away from the fire triangle, the fire will not start. And, a fire that is already burning will quickly go out. And firefighting relies on these principles, so it's really important that we understand the science behind how fires work. The fire will go out when the fuel runs out, for example. But, it's often really unsafe to leave a fire for that long and so different types of fires need to be tackled in slightly different ways. Katie: It's really interesting, sir. But, it's also so important to have this knowledge, isn't it? So that's why if you ever find yourself with a chip pan or oil fire, for example, you cover the pan with a damp cloth because that is removing the oxygen. Dr. Tim: Absolutely. You remove the oxygen from the fire triangle and the chip pan fire will go out. What are the three parts of the fire triangle? A fuel, oxygen and heat are needed for a fire. If one of these is removed, a fire will go out. What is a combustion reaction?Combustion is another word for burning. In a combustion reaction, a is heated and it reacts with oxygen. The fire triangle summarises the three things needed for combustion - a fuel, heat and oxygen. If one of these things is removed from a fire, the fire goes out. When fuels burn in combustion reactions, they release useful thermal energy (heat). Combustion reactions are used to heat our homes, power most cars, and to generate a lot of our electricity. A fire needs a fuel, oxygen, and heat What is the difference between combustion and burning? Nothing! They mean the same thing. Combustion is the scientific word for burning. Oxidation reactionsAn reaction is one where a substance reacts with oxygen and produces oxides. An oxide is a chemical compound that contains at least one oxygen atom and one other element in its chemical formula. Combustion is an example of an oxidation reaction. Many fuels contain carbon and hydrogen atoms. These fuels burn to produce oxides, carbon dioxide and water. Water, H₂O, is dihydrogen monoxide. Carbon dioxide, CO₂, is a that causes . Power station's emit carbon dioxide Water could also have the chemical name dihydrogen oxide or dihydrogen monoxide because two hydrogen atoms are bonded to one oxygen atom. Petrol is a fuel which is used in cars. Petrol is made from molecules which contain only carbon and hydrogen atoms. What is produced when petrol burns in a car engine? Carbon dioxide (CO₂) and water (H₂O) which are both oxides. Working scientificallyWorking safely with combustion in the lab Combustion reactions can be investigated in a science lab. If you are working with combustion it is important to work safely. To work safely, you need to identify hazards eliminate them, or if this isn't possible, control the risk. What safety precautions would you take to protect yourself when investigating combustion reactions?
These precautions will help reduce the risk of injury from the combustion investigation like getting burnt. Combustion equationsCombustion reactions can be described using word and symbol equations. The fuel used in gas barbeques is butane. Butane molecules contain only carbon atoms and hydrogen atoms and it is written as C₄H₁₀. When the butane burns, the carbon atoms react with oxygen in the air and carbon dioxide, and the hydrogen atoms react with oxygen to make water. The word equation for the combustion of butane is, butane + oxygen → carbon dioxide + water. The symbol equation for the combustion of butane is, C₄H₁₀ + O₂ → CO₂ + H₂O Like all combustion reactions, oxygen will always be one of the and be on the left of the equation. Most combustion reactions produce carbon dioxide and water, so these chemicals are written as the on the right of the equation. Gas barbeque using fuel to cook Charcoal is a fuel that contains carbon atoms but no hydrogen atoms. What is the word equation for the combustion reaction which occurs in a charcoal barbeque? Carbon + oxygen → carbon dioxide VideoWatch this video to see how a combustion reaction can be represented with a word and symbol equation. CH₄ is the formula for methane, the largest component of the natural gas used by the oven. This chef uses combustion daily when working with their oven I have a gas igniter here which I use everyday so I don't burn my fingers, because when I use matches, that's what happens. In the video, methane reacts with oxygen in a combustion reaction. What is the product? The product of the reaction is carbon dioxide (CO₂) and water (H₂O). Test your knowledgeWhat is the process of burning fuel to release energy called?In terms of chemistry, combustion is a chemical reaction in which an oxidant reacts rapidly with a fuel to liberate stored energy as thermal energy, most often in the form of high-temperature gases.
What is released when fuels burn in oxygen?Hydrocarbon fuels burn when they react with oxygen in the air. As all hydrocarbons only contain the elements carbon and hydrogen, the only products will be oxides of these elements. So as long as enough oxygen is present for complete combustion, the two products formed will be carbon dioxide (CO 2) and water (H 2O).
What is another word for burning fuel in oxygen?Combustion is another name for burning. In a combustion reaction, fuel is burned and reacts with oxygen to release energy.
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