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Log in through your institution journal article The Valence-State Energy of the Bivalent Oxygen AtomProceedings of the National Academy of Sciences of the United States of America Vol. 35, No. 5 (May 15, 1949) , pp. 229-232 (4 pages) Published By: National Academy of Sciences https://www.jstor.org/stable/88175 Read and download Log in through your school or library Alternate access options For independent researchers Read Online Read 100 articles/month free Subscribe to JPASS Unlimited reading + 10 downloads Journal Information PNAS is the world's most-cited multidisciplinary scientific serial. It publishes high-impact research reports, commentaries, perspectives, reviews, colloquium papers, and actions of the Academy. In accordance with the guiding principles established by George Ellery Hale in 1914, PNAS publishes brief first announcements of Academy Members' and Foreign Associates' more important contributions to research and of work that appears to a Member to be of particular importance. Publisher Information The National Academy of Sciences (NAS) is a private, nonprofit organization of the country’s leading researchers. The NAS recognizes and promotes outstanding science through election to membership; publication in its journal, PNAS; and its awards, programs, and special activities. Through the National Academies of Sciences, Engineering, and Medicine, the NAS provides objective, science-based advice on critical issues affecting the nation. Rights & Usage This item is part of a JSTOR Collection.
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Allied Solutions Class 8 Chemistry Solutions for Exercise in Chapter 5 - Language of ChemistryQ2) Define the term ‘valency’. With reference to water & ammonia as compounds respectively, state the valency of oxygen & nitrogen. Magnesium [[2, 8, 2]] has valency 2+. Give reasons. Answer: Solution: Valency is the number of particular atoms combined with or displaced with another atom to form a compound. Water which is H_2O, two atoms of hydrogen combine with one atom of oxygen. The valency of oxygen is 2, because it needs two atoms of hydrogen to form water. Ammonia which is NH_3 , One atom of nitrogen combines with 3 atoms of hydrogen. The valency of nitrogen is 3 because it needs 3 atoms of hydrogen to form ammonia. Magnesium has valency equal to 2^+ because the electronic configuration of Mg is [2,8,2]. The nearest noble gas to magnesium is neon with electronic configuration of [2,8], to achieve this stable electronic configuration Mg can lose 2 valence electrons, hence its valency is 2^+ .
Video transcript "in this video we are going to explore uh what the term valency is and with reference to water and ammonia as compounds respectively we are going to state the valency of oxygen and nitrogen and the third part of the question deals with magnesium so it says that magnesium has the electronic configuration two comma eight comma two and it's also given as the valency it has as two plus so we'll explore reasons as to why is it so so let's begin with um the first part of this question and that is to define the terminal you see if i have to say i can say valency is nothing but the combining power that an atom has when it forms a chemical compound or molecules so what does this mean this means that an atom is actually constantly trying to be in a stable state this is constant reach to try and be in a stable state and to do this it combines with different other atoms to form molecules or compounds or it gives away electrons or it takes electrons from other atoms to find that stable state this is one kind of a definition of valency you might come across another definition of valency that says uh valency is nothing but the number of hydrogen atoms that combine with other atoms to form compound so this second type of definition of valency is what i'll explain through with the examples in this video okay let's understand the formula to n square right quick revision we know that by the formula 2n square we can identify in each orbit the number of electrons so for the first three orbit we know it's 2 8 and 18. so if this is kind of satisfied that means the atom is in a stable state or it follows the octet rule right now let's look at the first compound that's asked over here and that is h2o or water now over here we know that there are two hydrogen atoms and one oxygen atom oxygen we know has the electronic configuration two comma six so the first orbit has two electrons so that's great that's the maximum amount of electrons that can uh be there in the first orbit the second orbit has six in actuality it needs to be eight to be stable right for oxygen to be stable it needs two electrons more in the second orbit where does it get these two electrons from it kind of shares this electrons with two of the hydrogen atoms hydrogen we know has just one electron in one orbit and in its own way to try and be stable hydrogen needs one more electron in the first orbit so what's happening over here is oxygen needs two electrons and that is being shared by hydrogen which in turn hydrogen receives its individual electrons to from the oxygen atom so in this case i can say oxygen has the valency too with respect to the compound water now uh go back to the definition that i said there's another definition that you can come across with respect to vacancy and that is the number of hydrogen atoms that combine with atoms to form compounds on this particular account the number of hydrogen atoms uses two so we can also say that the valency of oxygen is two okay let's uh look at this with another example another compound that they've given to us is ammonia right so ammonia we know is nh3 nitrogen we know has the atomic number seven so two in the first elec orbit two electrons in the first orbit and five electrons in the second orbit now if you see the first orbit is fine stable it can accommodate two electrons it has two electrons the second orbit can accommodate eight and in this case um it has only five so nitrogen will need three more electrons now these three electrons are shared by three hydrogen atoms okay so in this case i can say nitrogen has the valency three again going back to the second kind of definition of valency that i uh mentioned the number of hydrogen atoms that combine with other atoms to form a compound so the compound here is ammonia the number of hydrogen atoms that is actually combining with nitrogen is 3 right and if you see here the valency of nitrogen is three so we've defined valency we've seen the standard definition of the combining capacity of an of an atom that's termed as valency the number of electrons it can give take or share we saw a second kind of definition that relates to the number of hydrogen atoms and we've kind of touched based upon compounds like ammonia and water to kind of understand that a little bit now the third part of the question deals with magnesium so magnesium given to us is this the electronic configuration 2 comma 8 comma 2. first orbit two electrons great stable second orbit eight electrons great that's also fine third orbit has two electrons now in actuality uh the third orbit should have 18 electrons for any element to be stable right or any atom to be stable now it's very difficult uh to go and find another atom that would give 16 of its electrons to kind of help magnesium be stable and that will require a lot of energy for the electrons to move around right so the easiest way for magnesium is to give away these two electrons and reach a stable state by having the electronic configuration two comma eight now when magnesium gives away this two electrons it reaches the electronic configuration two comma eight which is nothing but of the nearest noble gas that is neon okay noble gas like we know are the most stable are the elements that are stable in the periodic table that have a stable electronic configuration and they follow the octet rule now if you pay attention here it says the valency is 2 plus yes we know that the number of electrons given by variation is two what does this plus sign have to say over here so a quick revision we know that in the nucleus of an error of an atom there are equal number of protons and equal number of electrons right so in case of magnesium protons would have been 12 electrons would have been 12. now magnesium gives away two electrons right so you have remaining ten electrons but the number of protons is twelve we know protons have a positive charge so the net charge of this particular element in which magnesium is giving away two electrons the net charge is positive right so that's the reason why we mention it as 2 plus or we can say write it as mg 2 plus which is nothing but it forms a cation it is giving away electrons and it is getting a positive charge the net charge of that atom becomes positive i hope uh you understood the three elements of this particular question and i will see you in the next question thank you " Was This helpful? Is the valency of oxygen 2 or 6?So, electronic configuration of oxygen is 2,6. It takes or accepts 2 electrons to achieve 8 electrons in its outermost shell to complete the octet and become stable. Hence the valency of oxygen is 2.
Why is oxygen valency 6?Solution : 1) Oxygen has 8 electrons in its atom. The distribution of electrons is 2, 6. <br> 2) The outer most shell consists 6 electrons, this number is hear to 8. <br> 3) Hence the valency of oxygen is `8-6=2.
Is the valency of oxygen is 0?Valency of Oxygen is +2 as it requires 2 electrons for octet configuration or the configuration as that of nearby Nobel element.
Does oxygen have valency 3?The valency of oxygen is 2, because it needs two atoms of hydrogen to form water.
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Valence of oxygen
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