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Petroleum Geochemical Survey
Published in Muhammad Abdul Quddus, Petroleum Science and Technology, 2021
Halogen-containing minerals are known as halite. Halogens are a group of five chemically similar elements, recorded in the seventh group of the periodic table. The periodic table is the arrangement of elements according to their atomic structure and characteristics. Naturally occurring minerals containing fluorine (F–), chlorine (Cl–), bromine (Br–) and iodine (I–) negative ions are termed as ‘halite salts’. The fifth element of the halogen group is astatine, which is not found in any minerals. About 100 halite minerals have been identified, but only a few of them are significant.
Introduction to Nanosensors
Published in Vinod Kumar Khanna, Nanosensors, 2021
The Periodic Table is a compilation of the chemical elements in ascending order of their atomic numbers to show the similarities of properties of elements. The vertical columns of the periodic table numbered I–VIII are called groups, while the horizontal rows 1–7 are known as periods. The groups contain elements that are similar to each other.
Crystal Clear
Published in Sharon Ann Holgate, Understanding Solid State Physics, 2021
If an atomic shell contains the maximum possible quota of electrons, it is said to be “full” or “closed,” and when the outermost shell of an atom is full, that atom is chemically stable and so will not react easily with other atoms. In fact, the last statement is slightly misleading, as atoms in which both the s subshell and the p subshell of the outermost shell are full are also unreactive and described as having full outer shells. (In discussions on bonding, whenever the outermost “shell” is referred to, it is a general term that, depending on the particular case, can mean either the entire outermost shell or the s and p subshells within the outermost shell.) If you look at the periodic table (see inside front cover), you will see that the noble gases—helium, neon, argon, krypton, xenon, and radon—which are all inert have full outer shells. Helium and neon have genuinely full outer shells, as He only has one s subshell, and this contains two electrons, while Ne has just an s and a p subshell in its outer shell, and both of these are full. Each of the other noble gases has full s and p subshells in its outermost shell.
Values in the Development of Early Periodic Tables
Published in Ambix, 2020
The periodic table is known for grouping together similar chemical elements and keeping dissimilar ones apart. In a similar vein, its origins offer fruitful grounds for inspecting similarities and differences. The systems of Newlands, Meyer, and Mendeleev were so alike that they all are recognised as competitors for the discovery of the same phenomenon – periodic dependency between various characteristics of chemical elements and their atomic weights. Yet, the systems appear very different.