Although coal is a complex mixture of substances, its elemental composition can be approximated by the formula c135h96o9ns. using this chemical formula, calculate the percentage, by mass, of carbon (c) in coal.

Nitric acid can be formed in two steps from the atmospheric gases nitrogen and oxygen, plus hydrogen prepared by reforming natural gas. in the first step, nitrogen and hydrogen react to form ammonia: (g) (g) (g) in the second step, ammonia and oxygen react to form nitric acid and water: (g) (g) (g) (g) calculate the net change in enthalpy for the formation of one mole of nitric acid from nitrogen, hydrogen and oxygen from these reactions. round your answer to the nearest .

What must be in balance for temperatures to remain constant?

What are several ways to reduce the effect of friction