Copper II Sulfide is formed when copper and sulfur are heated together. In this reaction, 172 g of copper reacts with 58 g of sulfur. After the reaction is complete, 19 g of sulfur still remains unreacted. What is the mass of copper sulfide formed?

in the given question, the partial pressure is calculated by using the ideal gas equation, that is, pv = nrt

here, p is pressure, v is volume = 25 l, n is number of moles = 0.0104 moles, r is gas constant = -0.0821 l.atm / mol.k

t is temperature = 273 k

p = nrt / v

p = (0.0104 mol × 0.0821 l.atm / mol.k × 273 k) / 25 l

= 0.0093 atm

i believe you are right for all except the 3rd ( look at sqdancefan his answer is much better)

answerspecific gravity;