When is di- used in the name of a hydrocarbon? when the main chain contains two carbon atoms
when there are two different substituents
when there are two main chains of equal length
when there are two identical substituents

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)

If 10.5 l of a at 0.98to 1.50 , is ?

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