1. Human saliva has a pH of 6 while the contents of the stomach has a pH of 2. How much greater is the concentration of hydrogen ions in the stomach over that in saliva

Asample of tin (ii) chloride has a mass of 0.49 g. after heating, it has a mass of 0.41 g.  what is the percent by mass of water in the hydrate?   %

What causes the appearance of lines in a emission spectrum

Temperature is defined as a. the equivalent of heat. b. a measure of the average kinetic energy of the individual atoms or molecules composing a substance. c. how hot or cold it is. d. the total kinetic energy of the atoms or molecules composing a substance. e. none of the above is correct.