Phosphoric acid (h3po4) has pka values of 2.14, 6.86 and 12.4. over what range of ph values would a solution containing both h2po4 - and hpo4 2- be an effective buffer?

Embryos of different species look very similar, which shows that the organisms share a ancestor.

List four observations that indicate that a chemical reaction may be taking place

Ammonia and oxygen react to form nitrogen monoxide and water, like this: 4nh3 (g) + 5o2 (g) → 4no (g) + 6h2o (g) also, a chemist finds that at a certain temperature the equilibrium mixture of ammonia, oxygen, nitrogen monoxide, and water has the following composition: compound pressure at equilibrium nh3 65.1atm o2 31.3atm no 62.7atm h2o 65.8atm compound pressure at equilibrium nh3 65.3 atm o2 7.79 atm no 12.1 atm h2o 65.8 atm calculate the value of the equilibrium constant kp for this reaction. round your answer to 2 significant