A 0.62g sample of sodium hydroxide and sodium carbonate and inert material was dissolved and required 30.00cm^3 of HCl to reach the phenolphthalein end point. Methyl orange point was added and 6.50cm^3 more HCl was required to reach the methyl orange point, if the HCl was 0.24M, calculate the percentage of sodium hydroxide and sodium carbonate in the sample.

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 .