Calculate the lattice energy (kj/mol) of the hypothetical ionic compound mx from the information given below. ie1(m) = 538 kj/molm(s) => m(g) δho = 74.4 kj/molδhof(mx) = -169.7 kj/molx2(g) => 2x(g) δh = 157 kjea (x) = -366 kj/molie1 (x) = 271 kj/mol

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.

Convert the temperature of dry ice, –77 ∞c, into degrees fahrenheit and kelvin.

As we move from left to right across the periodic table, what is the general trend? a) atomic radii increase. b) electronegavitiy decreases. c) nuclear shielding increases. d) metallic character decreases.