How many atoms of aluminum (Al) are in
3.15 mol of aluminum?
Answer in units of atoms

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.

What are the 4 phases of matter in order of increasing engery content?

Titration reveals that 11.6 ml of 3.0m sulfuric acid are required to neutralize the sodium hydroxide in 25.00ml of naoh solution. what is the molarity of the naoh solution?