Explosion - wikipedia Explosion `` Bomb blast '' redirects here. For the Bollywood movie, see Bomb Blast ( 1993 film ). `` Explosions '' redirects here. For the Ellie Goulding song, see Explosions ( song ). For the American post-rock band, see Explosions ( band ). For other uses, see Explosion ( disambiguation ). Look up explosion in Wiktionary, the free dictionary. This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. ( February 2014 ) Detonation of 16 tons of explosives. Gasoline explosions, simulating bomb drops at an airshow. Black smoke from an explosion rising after a bomb detonation inside the outside Nahr al - Bared, Lebanon. An explosion is a rapid increase in volume and release of energy in an extreme manner, usually with the generation of high temperatures and the release of gases. Supersonic explosions created by high explosives are known as detonations and travel via supersonic shock waves. Subsonic explosions are created by low explosives through a slower burning process known as deflagration. When caused by a human - made device such as an exploding rocket or firework, the audible component of an explosion is referred to as its `` report '' ( which can also be used as a verb, e.g., `` the rocket reported loudly upon impact '' ). Contents 1 Causes 1.1 Natural 1.1. 1 Astronomical 1.2 Chemical 1.3 Electrical and magnetic 1.4 Mechanical and vapor 1.5 Nuclear 2 Properties of explosions 2.1 Force 2.2 Velocity 2.3 Evolution of heat 2.4 Initiation of reaction 2.5 Fragmentation 3 Notable explosions 3.1 Chemical explosions 3.2 Nuclear explosions 3.3 Use in war 3.4 Volcanic eruptions 4 Etymology 5 See also 6 References Causes Natural Explosions can occur in nature. Most natural explosions arise from volcanic processes of various sorts. Explosive volcanic eruptions occur when magma rising from below has much - dissolved gas in it ; the reduction of pressure as the magma rises causes the gas to bubble out of solution, resulting in a rapid increase in volume. Explosions also occur as a result of impact events and in phenomena such as hydrothermal explosions ( also due to volcanic processes ). Explosions can also occur outside of Earth in the universe in events such as supernova. Explosions frequently occur during bushfires in eucalyptus forests where the volatile oils in the tree tops suddenly combust. Astronomical Among the largest known explosions in the universe are supernovae, which results when a star explodes from the sudden starting or stopping of nuclear fusion, and gamma ray bursts, whose nature is still in some dispute. Solar flares are an example of common explosion on the Sun, and presumably on most other stars as well. The energy source for solar flare activity comes from the tangling of magnetic field lines resulting from the rotation of the Sun 's conductive plasma. Another type of large astronomical explosion occurs when a very large meteoroid or an asteroid impacts the surface of another object, such as a planet. Chemical The most common artificial explosives are chemical explosives, usually involving a rapid and violent oxidation reaction that produces large amounts of hot gas. Gunpowder was the first explosive to be discovered and put to use. Other notable early developments in chemical explosive technology were Frederick Augustus Abel 's development of nitrocellulose in 1865 and Alfred Nobel 's invention of dynamite in 1866. Chemical explosions ( both intentional and accidental ) are often initiated by an electric spark or flame. Accidental explosions may occur in fuel tanks, rocket engines, etc. Electrical and magnetic A high current electrical fault can create an ' electrical explosion ' by forming a high energy electrical arc which rapidly vaporizes metal and insulation material. This arc flash hazard is a danger to persons working on energized switchgear. Also, excessive magnetic pressure within an ultra-strong electromagnet can cause a magnetic explosion. Mechanical and vapor Strictly a physical process, as opposed to chemical or nuclear, e.g., the bursting of a sealed or partially sealed container under internal pressure is often referred to as a ' mechanical explosion '. Examples include an overheated boiler or a simple tin can of beans tossed into a fire. Boiling liquid expanding vapor explosions are one type of mechanical explosion that can occur when a vessel containing a pressurized liquid is ruptured, causing a rapid increase in volume as the liquid evaporates. Note that the contents of the container may cause a subsequent chemical explosion, the effects of which can be dramatically more serious, such as a propane tank in the midst of a fire. In such a case, to the effects of the mechanical explosion when the tank fails are added the effects from the explosion resulting from the released ( initially liquid and then almost instantaneously gaseous ) propane in the presence of an ignition source. For this reason, emergency workers often differentiate between the two events. Nuclear Main articles : Nuclear explosion and Effects of nuclear explosions In addition to stellar nuclear explosions, a man - made nuclear weapon is a type of explosive weapon that derives its destructive force from nuclear fission or from a combination of fission and fusion. As a result, even a nuclear weapon with a small yield is significantly more powerful than the largest conventional explosives available, with a single weapon capable of completely destroying an entire city. Properties of explosions Force Explosive force is released in a direction perpendicular to the surface of the explosive. If a grenade is in mid air during the explosion and the direction of the blast will be 360 °. In contrast, in a shaped charge the explosive forces are focused to produce a greater local effect. Velocity The speed of the reaction is what distinguishes an explosive reaction from an ordinary combustion reaction. Unless the reaction occurs very rapidly, the thermally expanding gases will be moderately dissipated in the medium, with no large differential in pressure and there will be no explosion. Consider a wood fire. As the fire burns, there certainly is the evolution of heat and the formation of gases, but neither is liberated rapidly enough to build up a sudden substantial pressure differential and then cause an explosion. This can be likened to the difference between the energy discharge of a battery, which is slow, and that of a flash capacitor like that in a camera flash, which releases its energy all at once. Evolution of heat The generation of heat in large quantities accompanies most explosive chemical reactions. The exceptions are called entropic explosives and include organic peroxides such as acetone peroxide It is the rapid liberation of heat that causes the gaseous products of most explosive reactions to expand and generate high pressures. This rapid generation of high pressures of the released gas constitutes the explosion. The liberation of heat with insufficient rapidity will not cause an explosion. For example, although a unit mass of coal yields five times as much heat as a unit mass of nitroglycerin, the coal can not be used as an explosive ( except in the form of coal dust ) because the rate at which it yields this heat is quite slow. In fact, a substance which burns less rapidly ( i.e. slow combustion ) may actually evolve more total heat than an explosive which detonates rapidly ( i.e. fast combustion ). In the former, slow combustion converts more of the internal energy ( i.e. chemical potential ) of the burning substance into heat released to the surroundings, while in the latter, fast combustion ( i.e. detonation ) instead converts more internal energy into work on the surroundings ( i.e. less internal energy converted into heat ) ; c.f. heat and work ( thermodynamics ) are equivalent forms of energy. See Heat of Combustion for a more thorough treatment of this topic. When a chemical compound is formed from its constituents, heat may either be absorbed or released. The quantity of heat absorbed or given off during transformation is called the heat of formation. Heats of formations for solids and gases found in explosive reactions have been determined for a temperature of 25 ° C and atmospheric pressure, and are normally given in units of kilojoules per gram - molecule. A positive value indicates that heat is absorbed during the formation of the compound from its elements ; such a reaction is called an endothermic reaction. In explosive technology only materials that are exothermic -- that have a net liberation of heat and have a negative heat of formation -- are of interest. Reaction heat is measured under conditions either of constant pressure or constant volume. It is this heat of reaction that may be properly expressed as the `` heat of explosion. '' Initiation of reaction A chemical explosive is a compound or mixture which, upon the application of heat or shock, decomposes or rearranges with extreme rapidity, yielding much gas and heat. Many substances not ordinarily classed as explosives may do one, or even two, of these things. A reaction must be capable of being initiated by the application of shock, heat, or a catalyst ( in the case of some explosive chemical reactions ) to a small portion of the mass of the explosive material. A material in which the first three factors exist can not be accepted as an explosive unless the reaction can be made to occur when needed. Fragmentation Fragmentation is the accumulation and projection of particles as the result of a high explosives detonation. Fragments could be part of a structure such as a magazine. High velocity, low angle fragments can travel hundreds or thousands of feet with enough energy to initiate other surrounding high explosive items, injure or kill personnel and damage vehicles or structures. Notable explosions Further information : List of the largest artificial non-nuclear explosions Chemical explosions Nanaimo mine explosion 1887 Halifax Explosion 1917 Battle of Messines 1917 Oppau explosion, Ludwigshafen, Germany 1921 1944 Bombay explosion Port Chicago disaster 1944 RAF Fauld explosion 1944 Cádiz Explosion 1947 Texas City Disaster 1947 Nedelin catastrophe 1960 Soviet N1 rocket explosion 1969 Flixborough disaster 1974 PEPCON disaster, Henderson, Nevada 1988 AZF ( factory ), Toulouse, France 2001 Ryongchon disaster 2004 2005 Hertfordshire Oil Storage Terminal fire 2005 2008 Gërdec explosions Cataño oil refinery fire 2009 2015 Tianjin explosions 2015 Nuclear explosions Trinity test Castle Bravo Tsar Bomba Atomic bombings of Hiroshima and Nagasaki Use in war Artillery, mortars, and cannons Gunpowder and smokeless powder as a propellant in firearms and artillery Bombs Missiles, rockets, and torpedoes Atomic bombings of Hiroshima and Nagasaki Land mines, naval mines, and IEDs Satchel charges and sapping Hand grenades Volcanic eruptions Main article : Volcanic Explosivity Index Santorini Krakatoa Mount St. Helens Mount Tambora Mount Pinatubo Toba catastrophe theory Yellowstone Caldera Etymology Classical Latin explōdere means `` to hiss a bad actor off the stage '', `` to drive an actor off the stage by making noise '', from ex - ( `` out '' ) + plaudere ( `` to clap ; to applaud '' )... The modern meaning developed later : Classical Latin : `` to drive an actor off the stage by making noise '' hence meaning `` to drive out '' or `` to reject '' In English : Around 1538 : `` drive out or off by clapping '' ( originally theatrical ) Around 1660 : `` drive out with violence and sudden noise '' Around 1790 : `` go off with a loud noise '' Around 1882 : first use as `` bursting with destructive force '' See also Find more aboutExplosionat Wikipedia 's sister projects Definitions from Wiktionary Quotations from Wikiquote Combustion Deflagration Detonation Dust explosion Explosion protection Explosive limit Fuel tank explosion Implosion ( mechanical process ) : opposite of explosion Internal combustion engine Mushroom cloud Piston engine Plofkraak Standards for electrical equipment in potentially explosive environments Underwater explosion References Jump up ^ Kissane, Karen ( 2009 - 05 - 22 ). `` Fire power equalled 1500 atomic bombs ''. The Age. Melbourne. Archived from the original on 2009 - 05 - 27. Jump up ^ Dubnikova, Faina ; Kosloff, Ronnie ; Almog, Joseph ; Zeiri, Yehuda ; Boese, Roland ; Itzhaky, Harel ; Alt, Aaron ; Keinan, Ehud ( 2005 - 02 - 01 ). `` Decomposition of Triacetone Triperoxide Is an Entropic Explosion ''. Journal of the American Chemical Society. 127 ( 4 ) : 1146 -- 1159. doi : 10.1021 / ja0464903. PMID 15669854. Jump up ^ wikt : explode # Etymology GND : 4016009 - 9 LCCN : sh85046465 NARA : 10637806 NDL : 00560492 Retrieved from `` https://en.wikipedia.org/w/index.php?title=Explosion&oldid=841887104 '' Categories : Hazards Explosions Hidden categories : Articles needing additional references from February 2014 All articles needing additional references Wikipedia articles with GND identifiers Wikipedia articles with LCCN identifiers Wikipedia articles with NARA identifiers Wikipedia articles with NDL identifiers Talk Contents About Wikipedia Wikiquote Беларуская Български Bosanski Català Чӑвашла Čeština Dansk Deutsch Eesti Ελληνικά Español Esperanto فارسی Français 한국어 Հայերեն हिन्दी Hrvatski Ido Bahasa Indonesia Íslenska Italiano עברית ಕನ್ನಡ ქართული Қазақша Kiswahili Latviešu Bahasa Melayu Nederlands 日本 語 Norsk Occitan Polski Português Română Runa Simi Русский Simple English Slovenčina Slovenščina Soomaaliga Српски / srpski Srpskohrvatski / српскохрватски Svenska తెలుగు Türkçe Українська Tiếng Việt 粵語 中文 Kabɩyɛ 44 more Edit links This page was last edited on 18 May 2018, at 18 : 29 ( UTC ). 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Question: what is the difference between combustion and explosion
Answer: The speed of the reaction