The Arrhenius definition states that acids are substances which increase the concentration of hydronium ions ( H < sub > 3 </ sub > O < sup >+</ sup >) in solution.

An Arrhenius acid is a substance that increases the concentration of the hydronium ion, H < sub > 3 </ sub > O < sup >+</ sup >, when dissolved in water.

: H < sub > 2 </ sub > O ( l ) + H < sub > 2 </ sub > O ( l ) H < sub > 3 </ sub > O < sup >+</ sup >( aq ) + OH < sup >−</ sup >( aq )

In pure water the majority of molecules exist as H < sub > 2 </ sub > O, but a small number of molecules are constantly dissociating and re-associating.

Note that chemists often write H < sup >+</ sup >( aq ) and refer to the hydrogen ion when describing acid-base reactions but the free hydrogen nucleus, a proton, does not exist alone in water, it exists as the hydronium ion, H < sub > 3 </ sub > O < sup >+</ sup >.

Both theories easily describe the first reaction: CH < sub > 3 </ sub > COOH acts as an Arrhenius acid because it acts as a source of H < sub > 3 </ sub > O < sup >+</ sup > when dissolved in water, and it acts as a Brønsted acid by donating a proton to water.

There appeared to be no difference in the distribution of anti-A and anti-B activity in group O serum, though in two group O donors ( J. F. and E. M. ) only one type of agglutinin was found in the regions of low anionic binding capacity ( Figs. 1 and 2 ).

A sample of Fraction Af from group O plasma was dissolved in starting buffer, dialyzed against this buffer and subjected to chromatography using the gradient shown in Fig. 2.

Brackets indicate concentration, such that means the concentration of H < sub > 2 </ sub > O.

Antimony is stable in air at room temperature, but reacts with oxygen if heated to form antimony trioxide, Sb < sub > 2 </ sub > O < sub > 3 </ sub >.

Only a limited number of actinium compounds are known including AcF < sub > 3 </ sub >, AcCl < sub > 3 </ sub >, AcBr < sub > 3 </ sub >, AcOF, AcOCl, AcOBr, Ac < sub > 2 </ sub > S < sub > 3 </ sub >, Ac < sub > 2 </ sub > O < sub > 3 </ sub > and AcPO < sub > 4 </ sub >.

An amide is a compound with the functional group R < sub > n </ sub > E ( O )< sub > x </ sub > NR '< sub > 2 </ sub > ( R and R ' refer to H or organic groups ).

The term amide refers both to classes of compounds and to the functional group ( R < sub > n </ sub > E ( O )< sub > x </ sub > NR '< sub > 2 </ sub >) within those compounds.

The ensemble is generally represented as RC ( O ) NH < sub > 2 </ sub >.

Closely related and even more numerous are amides derived from primary amines ( R ' NH < sub > 2 </ sub >) with the formula RC ( O ) NHR '.

* The single verse, 2 Samuel 18: 33, regarding David's grief at the loss of his son (" And the king was much moved, and went up to the chamber over the gate, and wept: and as he went, thus he said, O my son Absalom, my son, my son Absalom!

For some elements, allotropes have different molecular formulae which can persist in different phases – for example, two allotropes of oxygen ( dioxygen, O < sub > 2 </ sub > and ozone, O < sub > 3 </ sub >), can both exist in the solid, liquid and gaseous states.

After the acceptance of Avogadro's hypothesis in 1860 it was understood that elements could exist as polyatomic molecules, and the two allotropes of oxygen were recognized as O < sub > 2 </ sub > and O < sub > 3 </ sub >.

As an example of different chemical behaviour, ozone ( O < sub > 3 </ sub >) is a much stronger oxidizing agent than dioxygen ( O < sub > 2 </ sub >).

# H < sub > 3 </ sub > O < sup >+</ sup >( aq ) + Cl < sup >−</ sup >( aq ) + NH < sub > 3 </ sub > → Cl < sup >−</ sup >( aq ) + NH < sub > 4 </ sub >< sup >+</ sup >( aq )

The species that gains the electron pair is the Lewis acid ; for example, the oxygen atom in H < sub > 3 </ sub > O < sup >+</ sup > gains a pair of electrons when one of the H — O bonds is broken and the electrons shared in the bond become localized on oxygen.

* The 1946 Paramount film O. S. S., starring Alan Ladd and Geraldine Fitzgerald, showed agents training and on a dangerous mission.

A sketch in the BBC comedy series Not the Nine O ' Clock News showed Scotland Yard's rotating sign being hand-cranked by the Commissioner.

In the second quarter, Neil O ' Donnell's controversial 5-yard touchdown pass to Kordell Stewart gave Pittsburgh a 10-6 halftime lead ( replays showed that Stewart stepped on the end line before making the catch, which would have made him ineligible ).

Markovnikov also showed that butyric and isobutyric acids have the same chemical formula ( C < sub > 4 </ sub > H < sub > 8 </ sub > O < sub > 2 </ sub >) but different structures ; i. e., they are isomers.

This study showed that, as the Si / O ratio is altered, the silicate crystals exhibit significant changes in their atomic arrangements.

In 1969, John S. O ' Brien showed that Tay – Sachs disease was caused by an enzyme defect ; he also proved that Tay – Sachs patients could be diagnosed by an assay of hexosaminidase A activity.

Sir Arthur Conan Doyle, who appeared in the prologue to the film based on his novel of the same name, reportedly showed a reel of O ' Brien's animation from the film to his friends, claiming it was real footage of living dinosaurs, to try to convince them that his story was based on fact.

According to Sam O ' Steen's memoir, Cut to the Chase, Mitchum showed up on set after a night of drinking and tore apart a studio office when they didn't have a car ready for him.

In 1938 George O White was made State Forester and following in the footsteps of Paul Dunn he took a truck equipped with a movie projector, screen and generator and showed forestry movies throughout the Ozark hill county.

The Pathé News people filmed " Little Mary O ' Connor " with her trained chicken, and showed the film around the country.

Lennon's inspiration for the song came when his son, Julian, showed him a nursery school drawing he called " Lucy-in the sky with diamonds ", depicting his classmate, Lucy O ' Donnell.

Using this method, he showed how to solve the Hamiltonian cycle problem in arbitrary n-vertex graphs by a Monte Carlo algorithm in time O ( 1. 657 < sup > n </ sup >); for bipartite graphs this algorithm can be further improved to time O ( 1. 414 < sup > n </ sup >).

In this position, O ' Leary won plaudits for declassifying Cold War-era records, which showed the U. S. Government had used American citizens as guinea pigs in human radiation experiments, as had long been rumored.

In fact, the Portuguese cinema showed particular interest in the fado universe in 1947 with O Fado, História de uma Cantadeira, starred by Amália Rodrigues or in 1963, with O Miúdo da Bica, starred by Fernando Farinha.

" O ’ Kelly believed that Newgrange, alongside the hundreds of other passage tombs built in Ireland during the Neolithic, showed evidence for a religion which venerated the dead as one of its core principles.

: O, rise, Finland, you showed to the world

In honor of O ' Connor's career, TV Land moved an entire weekend of programming to the next week and showed a continuous marathon of All in the Family.

During the commercial breaks TV Land also showed interview footage of O ' Connor and various All in the Family actors, producers with whom he had worked, and other associates.

In 1591, O ' Neill roused the ire of Bagenal by eloping with his sister, Mabel, but showed his loyalty to the crown with his military support for his brother-in-law in the defeat of Hugh Maguire at Belleek in 1593.

In 1861 he published Leaders of Public Opinion in Ireland, a brief sketch of the lives and work of Jonathan Swift, Henry Flood, Henry Grattan and Daniel O ' Connell, which showed great promise.

Documents released to The Irish Times showed that three of the four visits were connected with O ' Donoghue's attendance at race meetings in Cheltenham and Ascot.

Harpers in the old Irish tradition were still living as late as 1792, as ten, including Arthur O ' Neill, Patrick Quin and Donnchadh Ó Hámsaigh, showed up at the Belfast Harp Festival, but there is no proof of any of these being composers.