The crystal structure of sodium chloride (naci) is a simple cubic with the na and ci atoms alternating positions. each na atom is then surrounded by \ix ci atoms and likewise each c1 atom is surrounded by six na atoms. (a) sketch the atoms in a (100) plane. (b) assume the atoms arc hard spheres with nearest neighbors touching. the effective radius of na is i .0 a and the effective radius of ci is 1.8 a. determine the lattice constant. (c) calculate the volume dencity of na and c1 atoms. (d) calculate the mass density of nacl.

definition

                    entropy is a measure of the randomness or the extent of disorder of a chemical process.

                      enthalpy is a measure of the heat change of a reaction occurring at a constant pressure.

measurement units:

                        entropy is measured in joule per kelvin (jk⁻¹)   whereas enthalpy is measured in joule per mole (jmol⁻¹)

requirements:

                            entropy has no requirements or limits, and its change is measured by the division between the heat change of the chemical process and the temperature.

                              in contrast, enthalpy can only be related to the heat change of the reaction under standard conditions.

the answer is c

tell me if wrong