Of the well-characterized elements of group 7A, which would exhibit the following properties?
It reacts with the alkali metals (M) to form a salt MX, where X is the halogen. Its hydrogen halide, HX, forms an acidic solution. It is prepared by electrolysis from a molten salt. It forms interhalogen compounds only of the form XA, where A is the unknown and X is another halogen. 1. fluorine 2. chlorine 3. bromine 4. iodine
Why do the group 1 elements form ionic compounds?
Group 1 elements have 1 valence electron, meaning they have 1 extra electron that can easily be donated to an atom in search of 1 more electron. When they give away that extra electron to form an ionic compound, they become more stable.For example, Group 7A (Group 17) elements have 7 valence electrons, meaning they need 1 extra electron to be stable. Group 1 and 7A elements make splendid ionic compounds.
Why are group 1A elements always found in +1 oxidation state?
All alkali metals have the outer electronic configuration :ns1. When they loose an electron, they achieve the electronic configuration of the nearest noble gas. take Na , for example. Electronic configuration : 1s2 2s2 2p6 3s1. If it looses an electron, it will have neon's configuration : 1s2 2s2 2p6. If you notice , neon has a fully filled 2p subshell, thus making it exceptionally stable. So Na only needs to loose one electron to attain stability. You may say , "so what ? Why can't it loose another electron ?". There's a reason for that also. Well , when these elements loose an electron, the number of protons will exceed the number of electrons by 1. Thus , the force exerted by the nucleus on the other electrons (remaining) will increase, holding them even better than before. So loosing another electron will require a lot of energy. That's why the oxidation state of alkali metals is +1.Hope this helps !
What are the group 1A and group 7A elements examples of on the periodic table?
1A (s-block) and 7A(p- block ) are representative elements. Ex of 1A- Li, Na, K Ex of 7A--F, Cl, Br, I **
Why is hydrogen, a nonmetal, usually placed with group 1 elements in the periodic table even though it doesn't show a metallic property like the alkali metals?
The normal position of H in the periodic table is due strictly to its electron configuration being analogous to that of the alkali metals—that is, all elements in group 1A end in the ns1 electron configuration, containing 1 valence electron. In this position, all elements can lose the single valence electron to form a 1+ ion (although H+ by itself is never found, instead combining with H2O in acidic solutions or other elements/molecules to form an acid).However, the periodic table is just a simple model that can be modified as suited to explain chemical behavior. Since H has a single electron in its 1s orbital, it can also gain one electron to fill its energy level and form a 1- ion, mimicking the behavior of the halogens. It only forms such compounds with metals that have a lower electronegativity than it. It can also form a formal 1- oxidation number (not really a charge) when coupled with other less electronegative atoms such as in the compounds LiAlH4 and NaBH4, in which the H is not technically a 1- ion but formally is thought to have gained electron density. In all these cases, the compounds are strong reducing agents, and the H will quickly oxidize to its 1+ state. So, although I have seen some periodic tables with H also placed above F, this is much rarer behavior and does not fit in with the ns2 np5 electron configurations of the halogens.I have also seen tables with H also placed above C since, like the C family, it has a half-filled valence shell. This position also makes more sense in terms of its chemical behavior, although its electronegativity would probably best position it above B, since it is a non-metal and forms covalent bonds with other nonmetals.By the way, H is not the only element that does not follow the chemical properties of its family. In group 4A there are 3 different kinds of behavior. C is a non-metal (although graphite does conduct electricity due the way the C atoms bond); Si and Ge are both metalloids used extensively in computer chips for their semiconducting properties; Sn and Pb are both relatively weak metals. The only link is the ns2 np2 configuration.In the end, the periodic table is merely a way to organize the elements to help chemists make the most sense of their behavior.
Why is it that hydrogen (H) gets written after all elements, except those in Groups 6A or 7A?
If a substance is ionic then the convention is to write that cation first. This is why molecular formulas will be written as HF, HCl, etc. But molecules that are covalent in nature tend to be ranked either by electronegativity or whether they are the central atom of the molecular structure in an attempt to convey information about the structure. So, CH4, tells you C is the more electronegative of the group and is the central atom. The same would hold for NH4, SH6, and so on. In larger molecular formulas there are hints in the way they are written that also reflect the molecular structure. For example CH3COOH tells you there is a methyl group (CH3) bound to a carboxyl group (COOH), and that carboxyl group has an acidic H which is written at the very end. A variation of this is HCH3COO. It's the same molecule but with the acidic hydrogen at the beginning, just remember that it is still part of the carboxyl.
Why can hydrogen resemble the Group 1A and the Group 7A elements?
Group 1A---a single electron in the outer shell, which it can give up and have a valence of +1 Group 7A---a single electron in the outer shell, which it accept a second electron into and have a full shell and valence of -1
What are the groups 1A through 7A called on the periodic table?
1A-Alkali Metal 2A-Alkaline Earth Metal 3A-Boron Group 4A-Carbon Group 5A-Nitrogen Group 6A-Chalcogen 7A-Halogen Hope that helped.