Although aromatic substitution reactions usually occur by an electrophilic mechanism, aryl halides that have electron-withdrawing substituents can also undergo a nucleophilic substitution reaction, termed SNAr. The electron-withdrawing substituent(s) must be oriented ortho and/or para to the halogen. The reaction proceeds by nucleophilic attack of the nucleophile on the ring carbon bound to the halogen leaving group, an intermediate carbanion is formed which is termed a Meisenheimer complex. The Meisenheimer complex is stabilized via resonance by the electron-withdrawing groups. Expulsion of the halogen restores aromaticity to the ring and completes the reaction. Draw curved arrows to show the movement of electrons in this step of the mechanism.

The p sub shell can hold up to 8 electrons in an atom. true or false?

You have a sample of a gas that occupies a volume of 17ml at -111 degrees celsius. what volume does the sample occupy at 88 degrees celsius? show all work asap

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.