Ice melting is not a chemical change because .

A) a new reactant is formed
B) a new substance is not formed
C) a precipitate is no present
D) there is increased activation energy

What is the relationship of air masses and the temperature of oceans?

You mix the pks of succinic acid are 4.21 and 5.64. how many gramsa graduate student at sdsu wants to measure the activity of a particular enzyme at ph 4.0. to buffer her reaction, she will use a buffer system based on one of the acids listed below, which acid is most appropriate for the experiment? of monosodium succinate (fw = 140 g/mol) and disodium succinate (fw = 162 g/mol) must be added to 1 l of water to produce a solution with a ph 5.28 and a total solute concentration of 100 mm? (assume the total volume remains 1 liter, answer in grams monosodium succinate, grams disodium succinate, respectively.) volumes of 0.05 m nah2po4 and 0.05 m na2hpo4 (pk's for phosphoric acid are 2.15, 6.82 and 12.38). which of the following best describes the resulting solution?

Although respiratory organs vary across different organisms, they all contain respiratory surfaces that have a large surface area and are extremely thin. explain why having an extremely thin respiratory surface with a large surface area is advantageous for the process of gas exchange