Disks cool down more efficiently if their gas includes some molecular hydrogen — two
hydrogen atoms bonded together — rather than atomic hydrogen, which consists of only one atom.
In principle, the wave function, denoted by Greek letter psi, can be used to reveal these energy levels for any given atom or molecule, although in practice this has only been done for the very simplest — the hydrogen atom and molecule (made of two
hydrogen atoms bonded together).
Typically, and logically, a positively charged
hydrogen atom bonds to a negatively charged atom of oxygen, nitrogen or fluorine.
They differ from saturated fats by having fewer
hydrogen atoms bonded to their carbon chains.
Not exact matches
Methane — a compound made up of one carbon
atom bonded to four of
hydrogen — is, according to the Intergovernmental Panel on Climate Change, 25 times as potent as carbon dioxide.
Their composition is largely dependent on
hydrogen atoms in the molecules, and the ability of these to create
hydrogen bonds with other elements.
Nevertheless, a team from the University of Copenhagen's Department of Chemistry has managed to become the first to
bond positively charged phosphorus
atoms with positively charged
hydrogen ones.
The diamond - like structural unit consists of six - sided rings of carbon
atoms bonded together in chains surrounded by a halo of
hydrogen atoms.
They are also all saturated fats, chains of single -
bonded carbon
atoms with
hydrogen atoms neatly lined up on either side of each carbon.
Hydrogen atoms contained in water readily
bond with the heavy isotope to form hydrochloric acid gas, which then leaks into space — leaving more of the lighter isotope behind.
Like water, it is held together by the powerful
bonds between
hydrogen and oxygen
atoms, so ethanol can not travel through most petroleum pipelines.
At this temperature, the pressure in the reactor reaches 34 atmospheres, helping to break down the
bonds between the
hydrogen and carbon
atoms in the polymer chains.
Hydrogen atoms which diffuse inside the cages only
bond weakly to them, so the gas can be recovered simply by heating the material slightly.
Ethylene (or IUPAC name ethene) is the simplest alkene hydrocarbon, consisting of four
hydrogen atoms and two carbon
atoms connected by a double
bond.
The zirconium sapped the loyalty of the electrons
bonding the nitrogen pairs, weakening the link between the two
atoms and letting
hydrogen weasel in and latch onto the nitrogen.
He has spent his career focused on just one
bond, a link between a carbon and a
hydrogen atom in a molecule of methane, the main component of natural gas.
In recent years researchers have achieved better performance with compounds such as lithium borohydride, in which the metal
atoms form weaker, ionic
bonds with groups containing several
hydrogen atoms.
Instead of a hydrophilic alcohol group (an oxygen -
hydrogen molecule bound to a
hydrogen - saturated carbon
atom), the final lignin polymer contained a hydrophobic aldehyde group (a carbon
atom double -
bonded to an oxygen
atom).
Atoms of most elements, such as
hydrogen, oxygen and carbon, form tight chemical
bonds by sharing electrons with their neighbours in order to give each
atom a stable configuration of electrons.
Of the two types of
atom, oxygen has more pull on the electrons that they share to form the
bonds between them, so the oxygen becomes slightly negatively charged and the
hydrogens slightly positive.
For example, in water (H2O) the sole oxygen
atom is bound to two
hydrogen atoms, and the two
bonds constantly change in length.
Scientists from Tomsk Polytechnic University together with their colleagues from USA and Japan have proposed a novel way to address the most important and fundamental challenge of organic chemistry, i.e. breaking a
bond between carbon and
hydrogen atoms to form new organic substances.
Herein we demonstrate that a photoredox - mediated
hydrogen atom transfer protocol can efficiently and selectively install deuterium (D) and tritium (T) at α - amino sp3 carbon -
hydrogen bonds in a single step, using isotopically labeled water (D2O or T2O) as the source of
hydrogen isotope.
But chemists at the University of Copenhagen have discovered a new kind of
hydrogen bond that, at first glance, should be impossible: It's composed of two positively charged
atoms, one phosphorus and one
hydrogen.
Relying on a technique called infrared spectroscopy to explore the
bonds between
atoms, the researchers noticed it attaching to positive
hydrogen atoms.
The saying «opposites attract» certainly applies to
hydrogen bonds, which are made of one negatively and one positively charged
atom.
As the water boiled away, the
hydrogen escaped into interstellar space while the oxygen came back down and
bonded with carbon
atoms.
Normal ice is composed of water molecules, each made of an oxygen
atom bonded to two
hydrogen atoms.
It turns out that the answer lies in the interaction between the
bonds that hold the
atoms in the water molecule together and the much weaker
bonds, known as
hydrogen bonds, that are the glue holding groups of water molecules together.
Such interactions are dependent on chemical
bonds between
hydrogen atoms.
Melanie Sanford, a chemist the University of Michigan, Ann Arbor, who focuses on using metal - based agents, primarily palladium, to catalyze reactions that substitute
hydrogen in carbon -
hydrogen bonds with other
atoms or functional groups.
For example, instead of stealing an electron from double -
bonded carbons or a nearby propagating chain, the carbon
atom with the free radical sometimes steals an entire
hydrogen atom from another chain end.
Polyethylene consists of a chain of single -
bonded carbon
atoms, each still carrying its two
hydrogen atoms.
The result was a picture of the
bonds linking the carbon and
hydrogen atoms that make up the flat molecule pentacene.
For example, questions such as «What happens to the rest of the
bonds in a chain of carbon rings if you pinch a
hydrogen atom off the end?»
Again, the first one stripped off
hydrogens from adjacent carbon
atoms in both the long polyethylene chains and short alkanes to form double
bonds; the second split the molecules and randomly stitched split molecules back together.
DNA's twisted ladder structure requires rungs of
hydrogen bonds to hold it together; each
bond is essentially made up of a single
hydrogen atom that unites two molecules.
He knew he needed to find metals that were deft at breaking the carbon -
hydrogen bonds that are at the heart of methane, ethane, and propane, short hydrocarbons known as alkanes, and then add in oxygen
atoms that would transform the alkanes into alcohols.
Both materials were then sprayed with
hydrogen gas in which the
bonds were broken to form single
hydrogen atoms.
«The Ru catalyst precisely distinguishes butadiene and substituted acetylene molecules and new carbon - carbon
bonds are formed among a butadiene with two acetylenes just by migration of the terminal
hydrogen atoms in butadiene.
Water, for example, with one oxygen and two
hydrogen atoms, can form two
hydrogen bonds per molecule.
Inside the AlloSphere, researchers such as Van de Walle use a joystick to maneuver through three - dimensional constellations of the oxygen,
hydrogen and zinc
atoms (linked by a complex lattice of chemical
bonds) that make up these conductors.
Aspirin, for example, contains just 21
atoms (nine carbons, eight
hydrogens and four oxygens)
bonded together to form a particular shape.
When the methane is irradiated it is churned into ethane and other more complex organics (the molecule loses a
hydrogen bond and more carbon
atoms become chained together).
Almost as clearly as a textbook diagram, this image made by a noncontact atomic force microscope reveals the positions of individual
atoms and
bonds, in a molecule having 26 carbon
atoms and 14
hydrogen atoms structured as three connected benzene rings.
In the most common motif, created about 57 % of the time, hydroxide's oxygen
atoms bonded with the
hydrogen atoms on 4 water molecules while the hydroxide's
hydrogen bonded to the oxygen
atom on another water molecule.
Wiedner and Bullock focused on a cobalt catalyst and how it forms
bonds with
hydrogen atoms and shuffles electrons.
Methylene is the simplest member of a class of organic molecules known as carbenes, which contain an
atom of carbon only
bonded to two other
atoms, in this case, a pair of
hydrogen atoms.
Integral to the polymer's design are electron - withdrawing fluorine
atoms that create sites on the polymer with more positive
hydrogen atoms leading to stronger
hydrogen -
bonding interactions and more sensitive sensors.
The polymer and the agent form
hydrogen bonds, weak electrostatic connections between polymer's
hydrogen and an agent's oxygen
atom.