A compound frequently used as a high-temperature lubricant has the formula MS₂, where M represents some metallic element. If this compound is 40.06% sulfur by mass, what is the identity of the metal M?

Question

Quizplus · Accepted Answer

The formula given is MoS2, which is molybdenum disulfide, a common high-temperature lubricant. To find the metal, calculate the molar mass of MoS2 and determine the percentage of sulfur. Sulfur has an atomic mass of approximately 32.07 g/mol, so two sulfur atoms have a mass of 64.14 g/mol. Given that the compound is 40.06% sulfur, you can set up the equation 64.14 / (Molar mass of MoS2) = 0.4006 to find the molar mass of MoS2 and thus identify M as Mo (molybdenum).

A Compound Frequently Used as a High-Temperature Lubricant Has the Formula