Презентация, доклад по химии на тему: Сера на английском языке

sintered microcrystals
Standard atomicStandard atomic
weight (Ar, standard) [32.059, 32.076]
conventional: 32.06

conditions, sulfur atoms form cyclic octatomic molecules with a chemical formula S8.
Elemental sulfur is a bright yellow  crystalline solid at room temperature.
Chemically, sulfur reacts with all elements except for gold, platinum, iridium, tellurium, and the noble gases.

universe, and the fifth most common on Earth. Though sometimes found in pure, native  form, sulfur on Earth usually occurs as sulfide  and sulfate minerals. Being abundant in native form, sulfur was known in ancient times, being mentioned for its uses in ancient India,  ancient Greece, China, and Egypt.  Today, almost all elemental sulfur is produced as a byproduct of removing sulfur-containing contaminants from  natural gas  and petroleum.

a blue flame that is best observed in the dark.

​(115.21 °C, ​239.38 °F)

Boiling point 17.8 K ​(444.6 °C, ​832.3 °F)

Density alpha: 2.07 g/cm3  beta: 1.96 g/cm3  gamma: 1.92 g/cm3

which has a suffocating and irritating odor. Sulfur is insoluble in water but soluble in carbon disulfide and, to a lesser extent, in other nonpolar organic solvents, such as benzene and toluene.

example, by pouring it into cold water. X-ray crystallography studies show that the amorphous form may have a helical structure with eight atoms per turn. The long coiled polymeric molecules make the brownish substance elastic, and in bulk this form has the feel of crude rubber. This form is  metastable  at room temperature and gradually reverts to crystalline molecular allotrope, which is no longer elastic. This process happens within a matter of hours to days, but can be rapidly catalyzed.