<span>Among the given choices, which among them tells us the truth about the polyatomic ion. The polyatomic ions are charged molecules or formula units that are composed of many atoms. From the given choices, the answer would be letter C. It is made of atoms that are covalently bonded together. When we say covalently bonded, the atoms are shared among the atoms composing the formula unit. </span>
Answer:
the answer is c. [.4r]3d104324p
Gold has a heavy enough nucleus that its electrons must travel at speeds nearing the speed of light to prevent them from falling into the nucleus. This relativistic effect applies to those orbitals that have appreciable density at the nucleus, such as s and p orbitals. These relativistic electrons gain mass and as a consequence, their orbits contract. As these s and (to some degree) p orbits are contracted, the other electrons in d and f orbitals are better screened from the nucleus and their orbitals actually expand.
Since the 6s orbital with one electron is contracted, this electron is more tightly bound to the nucleus and less available for bonding with other atoms. The 4f and 5d orbitals expand, but can't be involved in bond formation since they are completely filled. This is why gold is relatively unreactive.
Hope it helps
Mass is an intensive physical property because it is dependent on the size of the sample.
