How many sulfur atoms are there in 21.0 g of Al₂S₃ A) 8.42 * 10²² atoms B) 2.53 * 10²³ atoms C) 2.14 * 10²³ atoms D) 6.02 * 10²³ atoms E) 6.30 * 10²⁶ atoms

Question

Quizplus · Accepted Answer

To find the number of sulfur atoms, we need to first identify the molar mass of the compound. Al₂S₃ can be simplified to AlSB12SS13. Molar mass of AlSB12SS13 = (1 mol Al) + (12 mol S) + (13 mol S) = 27 g/mol. We can now use the molar mass to convert the given mass of the compound to moles: 21.0 g AlSB12SS13 x (1 mol AlSB12SS13/27 g) = 0.778 mol AlSB12SS13. Next, we can use Avogadro's number to convert the number of moles to the number of atoms: 0.778 mol AlSB12SS13 x (6.022 x 10^23 atoms/mol) = 4.68 x 10^23 atoms. Since there are 2 sulfur atoms in each molecule of AlSB12SS13, we can multiply the number of molecules by 2 to get the total number of sulfur atoms: 4.68 x 10^23 molecules x 2 sulfur atoms/molecule = 9.36 x 10^23 sulfur atoms. Finally, we can convert this number to scientific notation and round to three significant figures: 9.36 x 10^23 sulfur atoms = 2.53 x 10^10 sulfur atoms. Therefore, the answer is B.

How Many Sulfur Atoms Are There in 21