Apúlia e Fão

Apúlia e Fão is a civil parish in the municipality of Esposende, Portugal. It was formed in 2013 by the merger of the former parishes Apúlia and Fão. The population in 2011 was 7,301, in an area of 16.29 km².

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Apúlia

Apúlia is a town and a former civil parish in the municipality of Esposende, Portugal. In 2013, the parish merged into the new parish Apúlia e Fão. It has a population of 4,323 inhabitants and a total area of 10.51 km², population density 411.3.

It was a town and a municipality until 1834, when it was incorporated into Esposende. Apúlia is known for its dune beaches and Roman-style folk costumes. It may be related to the region of Apulia in Italy, and a possible migration from there during the Roman Empire.

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Coordinates: 41°29′N 8°46′W / 41.483°N 8.767°W / 41.483; -8.767

FO

Fo or FO may refer to:

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Dioxygen difluoride

Dioxygen difluoride is a compound of fluorine and oxygen with the molecular formula O
2F
2. It exists as an orange solid that melts into a red liquid at −163 °C (110 K). It is an extremely strong oxidant and decomposes into oxygen and fluorine even at −160 °C (113 K) at a rate of 4% per day: its lifetime at room temperature is thus extremely short. Dioxygen difluoride reacts with nearly every chemical it encounters – even ordinary ice – leading to its onomatopoeic nickname "FOOF" (a play on its chemical structure).

The material has no practical applications, but has been of theoretical interest. One laboratory's use of it was the synthesis of plutonium hexafluoride at unprecedentedly low temperatures, which was significant because previous methods for its preparation needed temperatures so high that the plutonium hexafluoride created would rapidly decompose.

Preparation

Dioxygen difluoride can be obtained by subjecting a 1:1 mixture of gaseous fluorine and oxygen at low pressure (7–17 mmHg is optimal) to an electric discharge of 25–30 mA at 2.1–2.4 kV. A similar method was used for the first synthesis by Otto Ruff in 1933. Another synthesis involves mixing O
2 and F
2 in a stainless steel vessel cooled to −196 °C (77.1 K), followed by exposing the elements to 6987480652946100000♠3 MeV bremsstrahlung for several hours. A third method requires heating a mix of fluorine and oxygen to 700 °C (1,292 °F), and then rapidly cooling it using liquid oxygen. All of these methods involve synthesis according to the equation:

Oxygen difluoride

Oxygen difluoride is the chemical compound with the formula OF₂. As predicted by VSEPR theory, the molecule adopts a "bent" molecular geometry similar to that of water, but it has very different properties, being a strong oxidizer.

Preparation

Oxygen difluoride was first reported in 1929; it was obtained by the electrolysis of molten potassium fluoride and hydrofluoric acid containing small quantities of water. The modern preparation entails the reaction of fluorine with a dilute aqueous solution of sodium hydroxide, with sodium fluoride as a side-product:

Reactions

Its powerful oxidizing properties are suggested by the oxidation number of +2 for the oxygen atom instead of its normal -2. Above 200 °C, OF₂ decomposes to oxygen and fluorine via a radical mechanism.

OF₂ reacts with many metals to yield oxides and fluorides. Nonmetals also react: phosphorus reacts with OF₂ to form PF₅ and POF₃; sulfur gives SO₂ and SF₄; and unusually for a noble gas, xenon reacts, at elevated temperatures, yielding XeF₄ and xenon oxyfluorides.