Calculate the number of phosphorus atoms in a 70.0g sample of diphosphorus pentoxide (P2O5). Be sure your answer has a unit symbol if necessary, and round it to 3 significant digits.

How many atoms of oxygen are contained in 160 grams of n2o3

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.

This classification of drug typically changes the brain's chemistry and reduces its ability to create its own endorphins.