Electron affinity of halogens Electron gain Enthalpy

-

Electron Affinity (Electron gain Enthalpy) -

Halogens possess maximum electron affinities ( -ve electron enthalpies) in their respective periods, because of their small size and high effective nuclear charge. They require only one electron to complete their octct. Because of compact size, electron affinity of F is less than Cl. However, electron affinity decrease down the group from Cl to I. This is again due to increase in size of atoms.

Popular posts from this blog

Siemens Ozoniser how Siemens Ozoniser work

-
Image
Siemens Ozoniser:  This Ozoniser consist of two co-axial glass tubes fused together at one end. The outer side of the outer glass tube and the inner side of the inner glass tube are finally coated with tin foils as shown in the figure given below.  (Siemens Ozoniser)->2                                                     (Siemens Ozoniser)->1 These tin foil are connected  to the induction coil for supply of silent electric discharge. Pure and dry oxygen gas is passed into the apparatus through annular space. The gas is then subjected to the action of silent electric discharge where oxygen gets converted into ozone. The ozonised oxygen then comes out  of the apparatus through the outlet of the Ozoniser. (Siemens Ozoniser)->2
Read more

Rutile structure

-
Rutile structure: The radius radio is in the range 0.73 to 0.41. in rutile (TiO²) each Ti⁴+ ion is octahedrally surrounded by six O²- ions whereas each other O²- ion is surrounded by only three Ti⁴+ ions arranged at the tree corners of a plane triangle. The Co-ordination number of Ti⁴+ and O²+ ions are 6 and 3, respectively. It is not exactly a close packed structure. Ti⁴+ ions in rutile may however, be considered as forming a sufficiently distorted body centred cubic lattice.           Example  compounds  having radius ratio below 0.41 are SiO² and BeF² but these are only a few. The Co-ordination number of Si⁴+ and Be²+ is four and that of O²- is two. However, these are appreciably co-valent.
Read more

F - block element What are f - block elements

-
What are F - Block Elements - F - block elements are consist of Lanthanides and Actinides. In Lanthanides, they are 14 element immediately following Lanthanum (57) from cerium (58) to lutecium (71) . These 14 element are called Lanthanides . These Lanthanides belong to first inner transition series .           In Actinides , these are also 14 elements immediately following Actinium (89) starting from Thorium (90) to lawrencium (103) . The element from Th (90) to Lr (103) are called Actinides . They belong to second inner transition series.
Read more