Periodic Table and Elements

Sum of the first and second ionisation enthalpies (IE₁ + IE₂) for nickel is lesser as compared to that of platinum (Pt). 

Among the given elements, vanadium has the highest enthalpy of atomisation (515 KJ/mol).

All lanthanides are non-radioactive, except promethium. Uranium belongs to the family of rare earth elements, known as the actinides or actinoids.

5f orbital is more effectively shielded from nuclear charge than 4f orbital. Iron is the fourth most abundant element in the Earth's crust.

With 20 valence electrons, nickelocene, [Ni(η⁵-C₅H₅)₂], has the highest electron count of the transition metal metallocenes.

These measure the tendency of an atom to accept electrons. Therefore, atoms with high electronegativity and electron affinity readily form anion and hence ionic compounds.

Siderophiles exhibit a weak affinity, to both oxygen and sulphur. Siderophiles have an affinity for iron and a distinguishing characteristic of siderophiles is that, they exhibit high solubility in molten iron. Not abundant in the core or mantle, most siderophiles are thought to be richest, at the Earth's core. Platinum (Pt) group metals, including Ruthium (Ru), Rhodium (Rd), Palladium (Pd), Osmium (Os) and Iridium (Ir), exhibit a strong siderophile tendency.

Chalcophile elements have a high bonding affinity—usually in the form of covalent bonds—with sulfur, and are usually abundant in sulfides. Chalcophiles also exhibit a bonding affinity, with selenium, tellurium, arsenic, and antimony and therefore also exhibit high levels of derivatives, of these elements. When sulfur is abundant, chalcophile elements readily form sulfide minerals, as they precipitate from the magma. This process partially explains the formation of extensive deposits, of iron-nickel-copper sulfides.

Chalcophile elements have a high bonding affinity. Chalcophile elements are those metals and heavier non - metals that have a low affinity for oxygen and prefer to bond with sulpur as highly insoluble sulphides.

Both 1 and 2 are correct because , the electronic configuration of Au is given by  = Au = 4d¹⁰ 4f¹⁴ 6s¹.  The electronic configuration of Ag is given by = Ag = 4d¹⁰5s¹ . The electronic configuration of Cu is given by = Cu = 3d¹⁰ 4s¹   . The effective nuclear charge of Au increases  because of  poor shieiding effect  of 4f¹⁴  electrons (  lanthanoid contraction ) , due to which its ionization energy is higher in its group .  electronic configuration of Cu is given by  - 3d¹⁰4s¹ .  electronic configuration of K is given by - 4s¹3d⁰ . In Cu poor shielding effect of  3d¹⁰ electrons causes increase in effective nuclear charge and because of this IP value of Cu is greater than that of K . Hence, both the options are correct.

Lithium displays most of the characteristic properties of group to which it belongs. However, it differs in many respects from the remaining characteristic properties of the metals of Group 1.  Lithium has a diagonal relationship with magnesium and both have similarities in some of their characteristics.

With an increase in atomic size, the ionisation potential is reduced, since the distance of the outermost electron from the nucleus increases and hence the force of attraction decreases.

Alkaline Earth Metals are metals that are found in Group II of the periodic table. Six elements such as Beryllium, Magnesium, Calcium, Strontium, Barium and Radium are placed in this group.

There are two blocks of rare earths, the lanthanide series and the actinide series. Lanthanum and actinium are both located in group IIIB of the table. When one looks at the periodic table, one notices that the atomic numbers make a jump from lanthanum (57) to hafnium (72) and from actinium (89) to rutherfordium (104). If one skips down to the bottom of the table, one can follow the atomic numbers from lanthanum to cerium and from actinium to thorium, and then back up to the main body of the table. Some chemists exclude lanthanum and actinium from the rare earths, considering the lanthanides to start following lanthanum and the actinides to start following actinium.

Alkali metals are very reactive in nature. As they have one electron in their valence shell, they react very vigorously with air, oxygen, water and other substances in order to complete their octet.