This periodic table contains the oxidation numbers of the elements. Chemical Properties. The regular oxidation states showed by the elements of group 16 incorporate -2, +2, +4 and + 6. Stable Nuclei. Lv 5. • Helium is present in natural gas to an extent of 2%. Note: It has been pointed out to me that there are a handful of obscure compounds of the elements sodium to caesium where the metal forms a negative ion - for example, Na-.That would give an oxidation state of -1. immunitas. Bold numbers represent the more common oxidation states. Values in italics represent theoretical or unconfirmed oxidation numbers. Some chemical reactivity. ... Krypton is a member of group 18 (noble gases) elements. The group 16 elements, also known as the chalcogens have 6 valence electrons, and hence they can achieve noble gas configuration either by gaining 2 electrons or by sharing two electrons i.e., by forming M 2-ions, or forming two covalent bonds. Occurrence: • Except radon all the noble gases occur in free state in atmospheric air, sun, stars, natural gas etc. Interactive periodic table with up-to-date element property data collected from authoritative sources. In fact last member of the group, bismuth hardly forms any compound in –3 oxidation state. Relevance. These gases all have similar properties under standard conditions: they are all odorless, colorless, monatomic gases with very low chemical reactivity. 1 Answer. No chemical reactivity. 4. 3. • It is found in minerals in occluded form. $\endgroup$ – bobthechemist Sep 27 '13 at 20:04 $\begingroup$ @bobthechemist no , i mean that the oxidation states +1 and + 2 are stable for the alkali and the alkali earth metals respectively . Balbharati solutions for Chemistry 12th Standard HSC Maharashtra State Board chapter 7 (Elements of Groups 16, 17 and 18) include all questions with solution and detail explanation. Group 18th Elements(Zero group elements) 2 • Radon was discovered from the radioactive disintegration of radium. If you mean "the oxidation state +2 is stable for the elements of the alkali metals" then the statement is not correct. The tendency to exhibit –3 oxidation state decreases down the group due to increase in size and metallic character. The common oxidation states of these elements are –3, +3 and +5. You can ignore these if you are doing chemistry at A level or its equivalent. Group 18 (O) elements Kr & Xe have selected oxidation states other than zero. Look up chemical element names, symbols, atomic masses and other properties, visualize trends, or even test your elements knowledge by playing a periodic table game! Answer Save. This table also contains the element number, element symbol, element name and atomic weights of each element. The noble gases are a group of chemical elements that make up Group 18 on the periodic table. Unstable Nuclei. The stability of +5 oxidation state decreases down the group. Oxidation state 0 occurs for all elements – it is simply the element in its elemental form. 2. This indicates that they have? An element that is not combined with any other different elements has an oxidation state of 0. 1. This will clear students doubts about any question and improve application skills while preparing for board exams. Thus, these elements indicate both negative and positive oxidation states. All elements of the first transition series have oxidation state (+2) because after losing the electrons of (4s) sublevel at first (except for scadium), while in the higher oxidation states they lose the electron of (3d) in sequence..