Millions, Billions, Trillions !!!!
One mole of any substance, Arsenic included, contains 6.022 x 10^(23) atoms. #or 60,200,000,000,000,000,000,000 atoms.
As2S3 is written as diarsenic trisulfide. It consists of two atoms of arsenic and three atoms of sulfur bonded together.
The chemical formula of arsenic pentabromide is AsBr5. It consists of one arsenic atom bonded to five bromine atoms.
As all atoms do, arsenic has one nucleus. That nucleus consists of 33 protons and 42 neutrons.
Arsenic pentaiodide (AsI5) doesn't contain any metal; arsenic is a metalloid and iodine a nonmetal.
This compound is called tetraarsenic pentasulfide.
Assuming that the questioner meant "trifluoride" instead of "trifluride", there are four total atoms in the formula unit, AsF3.
Arsenic atoms are neutral and they form ions with valency of three.
As2S3 is written as diarsenic trisulfide. It consists of two atoms of arsenic and three atoms of sulfur bonded together.
The chemical formula of arsenic pentabromide is AsBr5. It consists of one arsenic atom bonded to five bromine atoms.
As all atoms do, arsenic has one nucleus. That nucleus consists of 33 protons and 42 neutrons.
Arsenic in AsO2 has one lone pair of electrons. This is because the arsenic atom has a steric number of 4, including 3 bonded atoms (two oxygen atoms and one other atom in the molecule) and 1 lone pair, following the octet rule.
Arsenic pentaiodide (AsI5) doesn't contain any metal; arsenic is a metalloid and iodine a nonmetal.
In one mole of Arsenic contains 6.02 x 10^23 atoms. This is the Avogadro's number. So in 3.5 moles of Arsenic, there would accordingly be 2.11 x 10^24 atoms.A mole of As has the Avogadro number of moles. It is equivalent to 6.022 x 10^23. Therefore, 3.5 moles of the element contains 2.11 x 10^24 atoms of Arsenic.
This compound is called tetraarsenic pentasulfide.
superconductor
In 3 formula units of (NH4)2HAsO4, there are 6 nitrogen (N) atoms, 24 hydrogen (H) atoms, 3 arsenic (As) atoms, and 12 oxygen (O) atoms. Each formula unit contains 2 nitrogen atoms, 8 hydrogen atoms, 1 arsenic atom, and 4 oxygen atoms. Therefore, multiplying by 3 gives the total number of atoms for each element.
The formula for arsenic tribromide is AsBr3. It consists of one arsenic atom bonded to three bromine atoms.