Choose each statement that is scientific. The universe's average temperature and rate of expansion support the idea that it began as one super-dense and hot mass 13.8 billion years ago.
The opinions of randomly selected participants in a survey prove the idea that global temperatures are not increasing on Earth.
Human life is more valuable than other forms of life on Earth because humans are more intelligent than other organisms.
Ocean tides are caused by the uneven gravitational pulls of the Moon and Sun on different parts of Earth.

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?

How many grams of oxygen gas are contained in a 15 l sample at 1.02 atm and 28°c? show your work.

Helium decays to form lithium. which equation correctly describes this decay?