Han purple,a synthetic inorganic pigment developed in China in ancient times,has the chemical formula BaCuSi₂O₆.What is its percent by mass silicon?

Question

Quizplus · Accepted Answer

To calculate the percent by mass of silicon, we need to find the molar mass of silicon in the compound and divide it by the molar mass of the entire compound, then multiply by 100. The molar mass of silicon is 28.0855 g/mol (from the periodic table), and the molar mass of the entire compound is 1131.1 g/mol. Therefore, the percent by mass of silicon is (28.0855/1131.1) x 100 = 2.48%. However, the question asks for the percent by mass of SiS, which has a molar mass of 96.198 g/mol. In the compound formula, there are two SiS units, so the total mass of SiS is 96.198 x 2 = 192.396 g/mol. Therefore, the percent by mass of SiS is (192.396/1131.1) x 100 = 15.9%, which is closest to choice B.

Han Purple,a Synthetic Inorganic Pigment Developed in China in Ancient