In 1911, Ernest Rutherford gave a model of the atom in which a central core held most of the atom's mass and a positive charge which, in units of the electron's charge, was to be approximately equal to half of the atom's atomic weight, expressed in numbers of hydrogen atoms.

All other nuclides ( isotopes of hydrogen and all other elements ) have more nucleons than electrons, so the fraction of mass taken by the nucleus is closer to 100 % for all of these types of atoms, than for hydrogen-1 .</ ref > with protons and neutrons having roughly equal mass.

Just six elements — carbon, hydrogen, nitrogen, oxygen, calcium, and phosphorus — make up almost 99 % of the mass of a human body ( see composition of the human body for a complete list ).

However, the law of mass action is valid only for concerted one-step reactions that proceed through a single transition state and is not valid in general because rate equations do not, in general, follow the stoichiometry of the reaction as Guldberg and Waage had proposed ( see, for example, nucleophilic aliphatic substitution by S < sub > N </ sub > 1 or reaction of hydrogen and bromine to form hydrogen bromide ).

Just six elements — carbon, hydrogen, nitrogen, oxygen, calcium, and phosphorus — make up almost 99 % of the mass of a human body ( see composition of the human body for a complete list ).

The lightest of the chemical elements are hydrogen and helium, both created by Big Bang nucleosynthesis during the first 20 minutes of the universe in a ratio of around 3: 1 by mass ( approximately 12: 1 by number of atoms ).

Except in the case of the isotopes of hydrogen ( which differ greatly from each other in relative mass — enough to cause chemical effects ), the isotopes of the various elements are typically chemically nearly indistinguishable from each other.

The 20 % range in relative mass among naturally occurring calcium isotopes is greater than for any element except hydrogen and helium.

* m < sub > H </ sub > is the mass of the hydrogen atom.

The debate was resolved in 1897 when J. J. Thomson measured the mass of cathode rays, showing they were made of particles, but were around 1800 times lighter than the lightest atom, hydrogen.

The atomic mass unit, 1 gram divided by Avogadro's number, is almost the mass of a hydrogen atom, which is mostly the mass of the proton.

Several estimates imply that practically all the matter, when measured by mass, in the visible universe ( not including dark matter ) is in the protons of hydrogen atoms, and that roughly protons exist in the visible universe ( Eddington number ), and roughly atoms exist in the visible universe.

Neutrons and other particles heavier than protons, as well as helium and other atoms with more than one proton, are so rare that their total mass in the visible universe is much less than the total mass of protons in hydrogen atoms.

Jupiter and Saturn consist mostly of hydrogen and helium, with heavier elements making up between 3 and 13 percent of the mass.

With an average atomic weight of ( for hydrogen-1 ), hydrogen is the lightest element and its monatomic form ( H < sub > 1 </ sub >) is the most abundant chemical substance, constituting roughly 75 % of the Universe's baryonic mass.

This left the early universe with a very similar ratio of hydrogen / helium as is observed today ( 3 parts hydrogen to 1 part helium-4 by mass ), with nearly all the neutrons in the universe trapped in helium-4.

All elements other than hydrogen and helium today account for only 2 % of the mass of atomic matter in the universe.

Because of helium's relatively low molar ( atomic ) mass, its thermal conductivity, specific heat, and sound speed in the gas phase are all greater than any other gas except hydrogen.

Lavoisier also formulated the law of Conservation of mass and discovered oxygen and hydrogen.

The idea is to trace out which think tanks are quoted by various mass media outlets within news stories, and to match these think tanks with the political position of members of the U. S. Congress who quote them in a non-negative way.

Shortly thereafter, Miyazaki proposed scenes in the screenplay for Flying Phantom Ship, in which military tanks would roll into downtown Tokyo and cause mass hysteria, and was hired to storyboard and animate those scenes.

By 22 June 1941 there were only 1, 475 T-34s and KV series tanks available to the Red Army, and these were too dispersed along the front to provide enough mass for even local success.

* Oxidiser tanks are very lightweight when empty, approximately 1 % of their contents, so the reduction in orbital weight by airbreathing is small, whereas air-breathing engines have a poor thrust / weight ratio which tends to increase the orbital mass.

In 1971 Lewis F. Powell Jr. urged conservatives to retake command of public discourse by " financing think tanks, reshaping mass media and seeking influence in universities and the judiciary.

These would be stored in tanks that would prevent a critical mass from forming by some combination of geometry or neutron absorption ( for example: long tubes made out of boron in an array with considerable spacing between tubes ).

On 14 February 1917 Colonel Macmullen of the GHQ staff, proposed that the plateau be taken by a mass tank attack, reducing the need for artillery ; in April a reconnaissance by Captain G. le Q Martel found that the area was unsuitable for tanks.

The Battle of Cambrai began on 20 November when the British breached the first two parts of the Hindenburg Line in the first successful mass use of tanks in a combined arms operation.

Gas turbines are also used in many liquid propellant rockets, the gas turbines are used to power a turbopump to permit the use of lightweight, low pressure tanks, which saves considerable dry mass.

* Fish tanks as thermal mass.

The city was partially destroyed by flood in 1865 and by both flood and fire in 1866 and again in 1882 ; on this last occasion, several oil tanks that were struck by lightning gave way, and Oil Creek carried a mass of burning oil into the city, where some 60 lives were lost and property valued at more than $ 1 million was destroyed.

The battle is often erroneously noted for being the first mass use of tanks in a combined arms operation.

During the 1970s the combined AISI Committees of Structural Steel Producers and Steel Plate Producers engaged in a series of research and promotional seminars and publication programs that focused, for example, on the use of steel storage tanks and transmission pipage in the water utility business, innovations in computer-aided design for structural steel frames for high-rise and arena buildings, applications for structural and steel plate in new mass transit system designs, and in utility poles for high voltage electrical transmission systems.

However, on January 26, 1931, I. Khalepsky ( Head of the Department of Mechanisation and Motorisation of the RKKA ) wrote a letter to S. Ginzburg with information obtained via the intelligence service that the Polish government had decided to purchase Vickers 6-Ton light infantry tanks as well as Christie M1931 cavalry tanks and to mass produce them with the assistance of both the British and French.

The La S was intended not just to train Germany's panzer troops, but to prepare Germany's industry for the mass production of tanks in the near future: a difficult engineering feat for the time.

In contrast, as a submarine expels water from its buoyancy tanks, it rises because its volume is constant ( the volume of water it displaces if it is fully submerged ) while its mass is decreased.

The SU-152 was the last member of the KV family of tanks in mass production, and was replaced by the ISU-152 on the ChKZ production lines in December 1943.

* Use of spherical tanks and stubby shape to reduce vehicle structural mass further.

He made arrangements for this to be grown in deep culture tanks at the Medical Research Council's Antibiotic Research Station in Clevedon, enabling mass production of this mould for the injections of the soldiers of World War II who suffered from infections.

For Project Highwater, tanks in SA-3's dummy upper stages were filled with of water, approximately, which was used to simulate the mass of future Saturn payloads.

This floating orientation is generally considered undesirable and can be minimized pre-dive by relocation of some of the weights ( perhaps of quick release type ) further to the rear ( such as in pockets close to the diver's cylinder ), and avoiding the use of aluminum tanks and using higher density cylinders ( typically steel ), which similarly moves the center of mass to be further behind the diver, and thus, behind the center of buoyancy.

This permits the use of low mass propellant tanks, permitting a high mass ratio for the rocket.