Which of the following statements best compares the pH value of H3PO4 and HCl? Both have a pH less than 7, but H3PO4 has a higher pH than HCl.
Both have a pH less than 7, but H3PO4 has a lower pH than HCl.
Both have a pH greater than 7, but H3PO4 has a higher pH than HCl.
Both have a pH greater than 7, but H3PO4 has a lower pH than HCl.

Two nitro no2 groups are chemically bonded to a patch of surface. they can't move to another location on the surface, but they can rotate (see sketch at right). it turns out that the amount of rotational kinetic energy each no2 group can have is required to be a multiple of ε, where =ε×1.010−24 j. in other words, each no2 group could have ε of rotational kinetic energy, or 2ε, or 3ε, and so forth — but it cannot have just any old amount of rotational kinetic energy. suppose the total rotational kinetic energy in this system is initially known to be 32ε. then, some heat is removed from the system, and the total rotational kinetic energy falls to 18ε. calculate the change in entropy. round your answer to 3 significant digits, and be sure it has the correct unit symbol.

0.2348 grams of pbcl2 used to form 44.0 ml of solution.

How are evaporation and sublimation similar? a both involve the formation of a gas. b both release energy to the surroundings. c both take place throughout a solid. d both take place at the surface of a liquid.