When 2.0 g copper is heated with an excess of sulfur, copper (I) sulfide is the product. What is the mass of the copper (I) sulfide produced? (mass to mass)

During which time interval does the object travel approximately 10 meters

What layer of the atmosphere is directly above the troposphere?

Given the following at 25c calculate delta hf for hcn (g) at 25c. 2nh3 (g) +3o2 (g) + 2ch4 (g) > 2hcn (g) + 6h2o (g) delta h rxn= -870.8 kj. delta hf=-80.3 kj/mol for nh3 (g), -74.6 kj/mol for ch4, and -241.8 kj/mol for h2o (g)