Question

Question 5 Each of the following elements has a positive electron affinity. In each case, construct its valence orbital energy diagram and use it to explain why the anion is unstable. a) N b) Mg c) Zn
need explanation not just answer

Answer 1

I www. - page of Q. Each of the following elements has a positive election affinity . In each case construct ito valence orbital energy diagram and use it to explain why the anion is unstable. Solh The election affinity (EA) of an element is defined as the energy required to add an electron to an atom or ion. when an atom going an election, it becomes a negative ion (anion). The positive electron affinity means that energy must be added to the system to produce an anion. (a) N Nitrogen (atomic number + 7) + (182 25² 2p3) [a] [av] H - Neutral 'N' atom IS 25 ap and unpaired as we can see the ap orbital is half-filled having same Same of all theree electrons. 2pore 2py 222 A - spin But when we add an eo and and make make N a an anion . how the electronic configuration changes to 18²28²2pq. since there are only 3 up orbital, the extral election goes to one of the p orbital with opposite spin. This Create electronic repulsion between the two electrones in the p-orbital, making the No in slightly unstable, hence require more energy to overcome this a repulsion.

Page-2 0 mg atomic no. 12 15² 25² 2p6 382) 2pre apy 26 - 15* 2s 2p 3s Here all Orbitals are completely filled haring paired electronic configuration (near to noble gas configuration). Hence electronic configuration of mg is very stable and if we add an extra eo to mg and form mg arion, then, IS 2s 2p 3s 3p The extrax election enters the orbital of 3p and make the configuration unpaired, and less stable. Hence extra energy would be needed therefor electron affinity is tve. © Zn + zine (atomic no -30) (182 28² 286 382 apo 452 od ²0) 30 R. Here gas and now inert orbital all orbitals are completely filled having an configuration. All electrons are paired in the electronic configuration is Nighly stable. it we add an extra eo to make an - 2 Pu upy 2/2 - Pu 3py 32 - 3 dny sdyz sluz 3 duhy? . anion IS 25 2p 3s 3p es 3d 3d22 ap apez now the electronic octronic configuration becon configuration become 15²28² 22838²3 p6 45²3doqp² and this make the zn anion undtable and need more energy filled > half filled > not completely filled Stability it completely order of o configuration.