Which substance will need 309 J of heat to warm 30g of the substance by a total of 25 °C?

Find the mass, in grams, of 5.00*10^23 molecules of f2

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)

What are the two basic types of satellites