Which element reacts violently with oxygen

Hydrogen is lighter than air, and was used in balloons and dirigibles also known as airships or zeppelins. Dirigibles were used in city-to-city air travel in the early s, and in trans-Atlantic crossings in the s and s. During World War I, German zeppelins were used in bombing runs over England, since they could fly higher than the British planes.

On May 6, , the German dirigible Hindenburg caught fire as it came in for a landing at Lakehurst Naval Air Station in New Jersey; 35 people out of the 97 aboard and one person on the ground were killed. The exact cause of the fire is still the subject of speculation, but the disaster signaled the beginning of the end for airship travel.

Modern "blimps" use helium to provide lift, which avoids the problem of hydrogen's flammability. Molecules which contain hydrogen bonded to nitrogen, oxygen, or fluorine can attract one another through the formation of hydrogen bonds. Hydrogen bonds are a particularly strong form of dipole-dipole forces , which arise because of the unequal sharing of electrons in some covalent bonds.

If one atom in a covalent bond is more electronegative than the other, it "pulls" harder on the electrons that the two atoms share, giving the more electronegative atom a partial negative charge, and the less electronegative atom a partial positive charge. The partially negative atom on one molecule attracts the partially positive atom on a neighboring molecule, causing the two molecules to be more attracted to each other than two nonpolar molecules which have no electronegativity differences between their bonded atoms would be.

Molecules that interact by these dipole-dipole forces tend to have higher boiling points than nonpolar molecules, because higher temperatures are necessary to overcome the attractive forces between the molecules and separate the molecules into the gas phase.

In the case of O—H, N—H, and F—H bonds, the electronegativity differences are particularly large because fluorine, oxygen, and nitrogen are the most strongly electronegative elements. The attractive forces between molecules containing these bonds are particularly strong, and are given the name hydrogen bonds. Hydrogen bonds are not as strong as covalent bonds, but they greatly influence the physical properties of many substances.

In particular, hydrogen bonds are responsible for the fact that water is a liquid at temperatures at which molecules of similar molecular mass are gases. For instance, hydrogen sulfide, H 2 S, which weighs Ice floats on liquid water because the hydrogen bonds hold the molecules into a more open, hexagonal array, causing the solid form to be less dense than the liquid form. In living systems, hydrogen bonding plays a crucial role in many biochemical process, from the coiling of proteins into complex three-dimensional forms to the structure of the DNA double helix, in which the two strands of DNA are held together by the hydrogen bonding between their nucleic acids components.

In this technique, a sample is placed in a powerful magnetic field usually produced by a superconducting magnet — see the section on Helium , which causes the hydrogen atoms in the sample to resonate between two different magnetic energy levels; pulsing the sample with a burst of radiofrequency radiation typically between to MHz causes the hydrogen atoms to absorb some of this radiation, producing a readout called an "NMR spectrum" which can be used to deduce a great deal of structural information about organic molecules.

Since almost all organic molecules contain hydrogen atoms, this technique is widely used by organic chemists to probe molecular structure; it can also be used to determine a great deal of information about extremely complex molecules such as proteins and DNA.

The technique is nondestructive, and only requires small amounts of sample. NMR spectroscopy can also be performed with the carbon isotope, and several other isotopes of other elements.

This technology is also used in an important medical imaging technique called Magnetic Resonance Imaging MRI ; the water molecules in different environments in the body respond to very slightly different magnetic field strengths, allowing images of tissues and organs to be obtained. This technique can be used in diagnosing cancers and creating images of tumors and other diseased tissues.

MRI is also used to study how the brain works by looking at what areas of the brain "light up" under different stimuli. The term "nuclear" is avoided in the medical application because of its unpleasant associations, even though the only radiation involved is similar to that of an FM radio transmitter.

Lithium is a soft, silvery metal, with a very low density, which reacts vigorously with water, and quickly tarnishes in air. The name of the element is derived from the Greek word for stone, lithos. It is found in the Earth's crust at a concentration of 20 ppm, making it the 31st most abundant element.

Lithium also presents some exceptions to the "typical" Group 1A behaviors. The lithium ion has a very high charge density because of its small size; thus, many lithium salts have significant covalent-bonding character, instead of being purely ionic. These salts dissociate less easily in water than the salts of sodium and potassium, and are therefore less soluble in water. In addition, lithium can form bonds to carbon which have high covalent character the organolithium compounds.

Lithium was one of the three elements produced in the Big Bang, although it was produced only in trace amounts. Aluminum and magnesium alloys of lithium are strong and lightweight; aluminum-lithium alloys are used in aircraft construction, trains, and bicycles.

Lithium-based batteries have very long lifetimes particular important in implantable devices such as pacemakers and defibrillators , and are very lightweight; they are frequently used in portable electronic devices and computers. Lithium salts such as lithium carbonate, Li 2 CO 3 are used in the treatment of bipolar disorder and some types of depression, and are also used to augment the actions of other antidepressants.

Lithium deuteride LiD, see entry on Hydrogen above is used in hydrogen bombs; neutrons produced by a fission-powered explosive are absorbed by the lithium atoms, transforming them into tritium; the fusion of tritium and deuterium to form helium releases tremendous amounts of energy.

Lithium hydroxide LiOH is used in confined spaces to remove carbon dioxide from the air the carbon dioxide is captured in the form of lithium carbonate ; this is particularly important in submarines and spacecraft.

There is no difference between the equations for the various elements in the Group whichever metal oxide or peroxide or superoxide you are using. These simple oxides all react with an acid to give a salt and water. For example, sodium oxide will react with dilute hydrochloric acid to give colourless sodium chloride solution and water. If the reaction is done ice cold and the temperature controlled so that it doesn't rise even though these reactions are strongly exothermic , a solution of the metal hydroxide and hydrogen peroxide is formed.

If the temperature increases as it inevitably will unless the peroxide is added to water very, very, very slowly! The reaction can be very violent overall. These reactions are even more exothermic than the ones with water. A solution containing a salt and hydrogen peroxide is formed. The hydrogen peroxide will decompose to give water and oxygen if the temperature rises - again, it is almost impossible to avoid this.

Another potentially violent reaction! This time, a solution of the metal hydroxide and hydrogen peroxide is formed, but oxygen gas is given off as well. Once again, these are strongly exothermic reactions and the heat produced will inevitably decompose the hydrogen peroxide to water and more oxygen. Again violent! Again, these reactions are even more exothermic than the ones with water. A solution containing a salt and hydrogen peroxide is formed together with oxygen gas.

The hydrogen peroxide will again decompose to give water and oxygen as the temperature rises. This is included on this page because of the similarity in appearance between the reactions of the Group 1 metals with chlorine and with oxygen. Sodium, for example, burns with an intense orange flame in chlorine in exactly the same way that it does in pure oxygen. The rest also behave the same in both gases. In each case, there is a white solid residue which is the simple chloride, XCl.

There is nothing in any way complicated about these reactions! If this is the first set of questions you have done, please read the introductory page before you start. The Reactions with Air or Oxygen General These are all very reactive metals and have to be stored out of contact with air to prevent their oxidation. Details for the individual metals Lithium Lithium burns with a strongly red-tinged flame if heated in air. Sodium Small pieces of sodium burn in air with often little more than an orange glow.

The equation for the formation of the simple oxide is just like the lithium one. The peroxide equation is: Potassium Small pieces of potassium heated in air tend to just melt and turn instantly into a mixture of potassium peroxide and potassium superoxide without any flame being seen. This is known as tarnishing. Lithium tarnishes slowly due to its relatively slow reaction with oxygen.

Sodium tarnishes more quickly than lithium, which is further evidence for the greater reactivity of sodium when compared to lithium. Metal oxides, peroxides, and superoxides dissolve in water actually react with water to form basic solutions.

Oxygen also forms covalent oxides with non-metals, that react with water to form acidic solutions. Oxygen does not react with fluorine or noble gases. Exceptions to all of these trends are discussed below.

Reactions with Group 1 Elements Oxygen reacts rapidly with Group 1 elements. Potassium Small pieces of potassium heated in air tend to melt instantly into a mixture of potassium peroxide and potassium superoxide with no visible flame. Reactions with Group 2 Elements The elements of Group 2 are beryllium, magnesium, calcium, strontium, barium, and radioactive radium. Beryllium Beryllium is unreactive with air and water.

All other group 2 metals Except beryllium, the other alkaline earth metals form oxides in air at room temperature. Reactions with Group 13 Elements Group 13 consists of the following elements: boron, aluminum, gallium, indium, and thallium. Reactions with Group 14 Elements Group 14 is made up of both metals toward the bottom of the group , metalloids, and nonmetals at the top of the group. Carbon monoxide is only slightly soluble in water and does not react with it.

Click here for more Information. The three metals in this group have many different oxide compounds due to their extended octets.

All of these oxides are amphoteric exhibit both basic and acidic properties. The easiest to remember and draw is based on a diamond structure with each of the silicon atoms being bridged to its other four neighbors via an oxygen atom. Reactions with Group 15 Elements The nitrogen family, Group 15 , is capable of reacting with oxygen in many different ways.

Reactions with Group 16 Elements The elements in Group 16 include oxygen, sulfur, selenium, tellurium, and polonium. Oxygen Although oxygen is located in Group 16 , it is unique in its extreme electronegativity; this allows it to readily gain electrons and create hydrogen bonds. Reactions with Group 17 Elements The elements in Group 17 include fluorine, chlorine, bromine, and iodine.

Fluorine : The most electronegative element adopts the -1 oxidation state. Reactions with Group 18 Elements The Group 18 noble gases include helium, neon, krypton, xenon, and radon. References Reactions of Selenium and Oxygen.

General Chemistry: Principles and Modern Applica tions - 9th ed. Upper Saddle River: Prentice Hall, Zumdahl, Steven S. Chemical Principles - 5th ed. Houghton Mifflin Company, Madsen, Dorte. Class Lecture Notes. Main Group Elements. University of California, Davis, California. Spring Problems If there are 4. Which noble gas es , if any, react with oxygen?