Hydrogen how many atoms

Hydrogen was the unwitting discovery of Paracelsus, the sixteenth century Swiss alchemist also known as Theophrastus Philippus Aureolus Bombastus von Hohenheim. He found that something flammable bubbled off metals that were dropped into strong acids, unaware of the chemical reaction that was forming metal salts and releasing hydrogen, something a number of others including Robert Boyle would independently discover over the years.

However, the first person to realize hydrogen was a unique substance, one he called 'inflammable air,' was Henry Cavendish, the noble ancestor of William Cavendish who later gave his name to what would become the world's most famous physics laboratory in Cambridge.

Between the s and s, Henry not only isolated hydrogen, but found that when it burned it combined with oxygen or 'dephlogisticated air' as it was called to produce water. These clumsy terms were swept aside by French chemist Antoine Lavoisier who changed chemical naming for good, calling inflammable air 'hydrogen', the gene, or creator, of hydro, water.

Because hydrogen is so light, the pure element isn't commonly found on the Earth. It would just float away. The prime components of air, nitrogen and oxygen, are fourteen and sixteen times heavier, giving hydrogen dramatic buoyancy. This lightness of hydrogen made it a natural for one of its first practical uses - filling balloons. No balloon soars as well as a hydrogen balloon.

The first such aerial vessel was the creation of French scientist Jacques Charles in , who was inspired by the Montgolfier brothers' hot air success a couple of months before to use hydrogen in a balloon of silk impregnated with rubber. Hydrogen seemed to have a guaranteed future in flying machines, reinforced by the invention of airships built on a rigid frame, called dirigibles in the UK but better known by their German nickname of Zeppelins, after their enthusiastic promoter Graf Ferdinand von Zeppelin.

These airships were soon the liners of the sky, carrying passengers safely and smoothly across the Atlantic. But despite the ultimate lightness of hydrogen it has another property that killed off airships - hydrogen is highly flammable. The destruction of the vast zeppelin the Hindenburg, probably by fire caused by static electricity, was seen on film by shocked audiences around the world. The hydrogen airship was doomed. Yet hydrogen has remained a player in the field of transport because of the raw efficiency of its combustion.

Many of NASA's rockets, including the second and third stages of the Apollo Program's Saturn V and the Space Shuttle main engines, are powered by burning liquid hydrogen with pure oxygen.

More recently still, hydrogen has been proposed as a replacement for fossil fuels in cars. Here it has the big advantage over petrol of burning to provide only water. No greenhouse gasses are emitted. The most likely way to employ hydrogen is not to burn it explosively, but to use it in a fuel cell, where an electrochemical reaction is used to produce electricity to power the vehicle.

Not everyone is convinced that hydrogen fuelled cars are the future, though. We would need a network of hydrogen fuel stations, and it remains a dangerous, explosive substance. At the same time, it is less efficient than petrol, because a litre of petrol has about three times more useful energy in it than a litre of liquid hydrogen if you use compressed hydrogen gas that can go up to ten times more.

The other problem is obtaining the hydrogen. It either comes from hydrocarbons, potentially leaving a residue of greenhouse gasses, or from electrolysing water, using electricity that may not be cleanly generated. But even if we don't get hydrogen fuelled cars, hydrogen still has a future in a more dramatic energy source - nuclear fusion, the power source of the sun. Fusion power stations are tens of years away from being practical, but hold out the hope of clean, plentiful energy.

However we use hydrogen, though, we can't take away its prime position. It is numero uno, the ultimate, the king of the elements. So it's the most abundant element, is essential for life on earth, fuels space rockets and could resolve our fossil fuel dependents.

You can see why Brian Clegg classes hydrogen as number one. Now next week we meet the time keeper of the periodic table. One current use is in atomic clocks, though rubidium is considered less accurate than caesium. The rubidium version of the atomic clock employs the transition between two hyperfine energy states of the rubidium isotope.

These clocks use microwave radiation which is tuned until it matches the hyperfine transition, at which point the interval between wave crests of the radiation can be used to calibrate time itself. Until then I'm Meera Senthilingam, thanks for listening and goodbye. Chemistry in its element is brought to you by the Royal Society of Chemistry and produced by thenakedscientists. There's more information and other episodes of Chemistry in its element on our website at chemistryworld.

Click here to view videos about Hydrogen. View videos about. Help Text. Learn Chemistry : Your single route to hundreds of free-to-access chemistry teaching resources. We hope that you enjoy your visit to this Site. We welcome your feedback. Data W. Haynes, ed. Version 1. Coursey, D. Schwab, J. Tsai, and R. Dragoset, Atomic Weights and Isotopic Compositions version 4. Periodic Table of Videos , accessed December Podcasts Produced by The Naked Scientists.

Download our free Periodic Table app for mobile phones and tablets. Explore all elements. D Dysprosium Dubnium Darmstadtium. E Europium Erbium Einsteinium. F Fluorine Francium Fermium Flerovium. G Gallium Germanium Gadolinium Gold.

I Iron Indium Iodine Iridium. K Krypton. O Oxygen Osmium Oganesson. U Uranium. V Vanadium. X Xenon. Y Yttrium Ytterbium. Z Zinc Zirconium.

Membership Become a member Connect with others Supporting individuals Supporting organisations Manage my membership. Facebook Twitter LinkedIn Youtube. Discovery date. Discovered by. Henry Cavendish. Origin of the name. The name is derived from the Greek 'hydro' and 'genes' meaning water forming. Melting point. Boiling point. Atomic number. Relative atomic mass. Key isotopes. Electron configuration. CAS number. ChemSpider ID. ChemSpider is a free chemical structure database.

Electronegativity Pauling scale. Covalent bond. Found in. A mole Avogadros number is the number that is equivalent to the number of atoms in 12 grams of pure carbon, which is always 6. Hydrogen has an atomic weight of 1. An even smaller proportion of hydrogen atoms are the isotope tritium , or hydrogen-3, which has one proton and two neutrons.

These isotopes with an additional neutron add a tiny amount to hydrogens average atomic weight. The atomic weight of hydrogen is 1. A hydrogen, nitrogen, or oxygen molecule, consists of two identical atoms of each of those respective elements. Therefore, a hydrogen molecule's mass is 2 amu, oxygen is 32 amu and nitrogen is 28 amu. Now let's talk about what is meant by a MOLE of a substance It works like this. A MOLE of any substance has the same numerical value for the number of grams it contains as the number of atomic mass units amu.

Furthermore, a MOLE of a substance contains a fixed number of atoms or molecules. That number is called Avagadros number and is equal to 6. However, one mole of hydrogen atoms has a mass of 1 gram while one MOLE of hydrogen molecules has a mass of 2 grams. Recall that two hydrogen atoms bind to make a hydrogen molecule. The same can be said of one mole of any other substance where two atoms combine to make a simple molecule. A mole of oxygen atoms 16 grams while a mole of oxygen molecules is 32 grams.

A mole of nitrogen atoms is 14 grams and a mole of nitrogen molecules 28 grams, etc. Reminder: Atoms are very small. Most of the atom is concentrated in its nucleus whose diameter is roughly 10 centimeters, but atoms are surrounded by "clouds" of electrons that extend out to 10 -8 centimeters.

The notation means 10 to the exponent or -8, respectively. See Appendix A2 for more details on exponentials. So atomic sizes are often reckoned in terms of the size of the electron cloud. The distance between closely packed atoms is also taken to be about 10 -8 centimenters. The Ideal Gas Model is useful for understanding the properties of gases.

It is not necessary to have a detailed understanding of atoms or molecules. In this model, a gas consists of a very large number of atomic particles viewed as indestructible tiny spheres that collide elastically with each other. The distance between these particles in a gas is large compared to the particles themselves. A "model" of a physical process is used to represent what one actually observes, even though this is an "ideal" model and not expected to be correct in all respects.

However, it is a good enough model to explain many of the properties of gases with sufficient accuracy. The motion of gas particles can be used to explain the pressure exerted and the temperature of a gas. The pressure on a surface is due to the force on that surface divided by its area.