sanyojakata

tatvon ki sanyojan shakti (combining power) ko sanyojakata (Valency) ka naam diya gaya hai. sanyojakata ka yathaarth gyaan hi samast rasaayan shaastr ki neenv hai. pichhle varsho mein dravyon ke svabhaav tatha gunon ka adhik gyaan hone ke saath saath sanyojakata ke gyaan mein bhi vruddhi hui hai.

doosare shabdon mein, sanyojakata ek sankhya hai jo yeh pradarshit karti hai ki jab koi parmaanu kitne ilektraun praapt karta hai, ya khota hai ya saajha karta hai jab vah apne hi tatv ke parmaanu se ya kisi anya tatv ke parmaanu se bandhan banaata hai.

anukram

itihaas

19veen shataabdi ke lagbhag madhyakaal mein angrej rasaayanajnya frainkalaind (Frankland) tatha jarman rasaayanajnya kaulbe (Kolbe) ne sanyojakata ke vishay mein apni kalpanaaeain vyakt keen. frainkalaind ne pradarshit kiya ki akaarbanik (inorganic) yaugikon mein praaya: ek keindreeya tatv anya tatvon ke nishchit tulyaankon se sanyog karta hai. udaaharan ke liye, naaitrojan, fausforas tatha aarsenik ka ek parmaanu haaidrojan tatha kloreen ke teen athva paaainch paramaanuon se sanyog karke yaugik banaata hai. is prakaar aisa prateet hota hai ki sanyukt haanevaale tatvon ki sanyojanashakti sadaiv anya paramaanuon ki nishchit sankhya se santusht ho sakti hai. ataev yadi haaidrojan ki sanyojakata ko ikaai maan liya jaae, to kisi tatv ki sanyojakata haaidrojan paramaanuon ki un sankhyaaon ke baraabar hogi jinke saath us tatv ka parmaanu sanyog kar sakta hai. udaaharanaarth, kloreen, okseejan paramaanuon ki un sankhyaaon ke baraabar hogi jinke saath us tatv ka parmaanu sanyog kar sakta hai. udaaharanaarth, kloreen, okseejan tatha kaarban ka ek parmaanu haaidrojan ke kramash: ek, do, teen tatha chaar paramaanuon se sanyog karta hai. isliye kloreen, okseejan, naaitrojan tatha kaarban ki sanyojakataaeain kramash: ek, do, teen tatha chaar hain. kuchh tatv haaidrojan ke saath sanyog naheen karte. aise tatvon ki sanyojakata, kloreen ya okseejan ki sanyojakata ko kramash: ek ya do maankar, nikaali ja sakti hai. udaaharan ke liye thoriym ka ek parmaanu kloreen ke chaar tatha okseejan ke do paramaanuon se sanyog karta hai. at: thoriym ki sanyojakata chaar hai.

praaya: tatvon ki sanyojakata ko rekhaaon dvaara dikhaaya jaata hai. in rekhaaon ko 'sanyojakata bandhan' (Valency bonds) kaha ja sakta hai.

prasiddh kaarbanik rasaayanajnya kekoole (Kekule) ke vichaar bhi frainkalaind ke vichaaron se milte julate the. keval ek baat mein donon mein teevr matabhed tha. jaisa uparyukt vivran se spasht hai, akaarbanik yaugikon mein bahudha ek hi tatv ki sanyojakata vibhinn yaugikon mein bhinn ho sakti hai. udaaharan ke liye, PCI3 tatha PCI5 yaugikon mein fausforas ki sanyojakata kramash: teen tatha paaainch hai. iske vipreet kaarbanik yaugikon mein, jo adhiktar kaarban, haaidrojan, okseejan tatha naaitrojan ke sanyog se bane hote hain, in tatvon ki sanyojakata sthir aur sab kaarbanik yaugikon mein kramash: chaar, ek, do tatha teen, hoti hai. inki sanyojakataaon mein saadhaaranataya kabhi antar naheen hota.

sanyojakata ke baare mein spasht gyaan praapt hone se rasaayanajnyaon ko tatvon ke paramaanubhaar nikaalne mein bahut sahaayata mili hai. kisi bhi tatv ka paramaanubhaar uske tulyaanki bhaar aur sanyojakata ke gunanafal ke baraabar hoga. tatvon ke tulyaanki bhaar prayogon dvaara saralata se nikaale ja sakte hain. unneesaveen shataabdi ke chauthe bhaag mein, jab roosi mahaan‌ vaigyaanik meindeleef (Mandeleef) ne aavart saarani (Periodic Table) ka varnan kiya, to unhonne saath hi saath us saarani mein kisi tatv ki sthiti aur usaki sanyojakata ka sambandh bhi suspasht kiya. tatvon ko unke paramaanubhaar ke kram se rakhane par, pratyek tatv apne se aathavein tatv ke saath bhautik tatha raasaayanik gunon mein samaanata pradarshit karta hai. is prakaar nishkriya gaison ke aavishkaar ke baad, vartamaan aavart saarani nau samoohon mein baint jaati hai. inmein nishkriya gaison, jaise heeliym, neean, aagann, kriptan, jeenan tatha raidan ka samooh shoonya samooh kahalaata hai, kyonki ye tatv kisi bhi anya tatv ke prati saadhaaranataya sanyojanashakti naheen pradarshit karte. agala samooh ailakaili ya kshaareeya dhaatuon (jaise leethiym, sodiym, potaishiym aadi) ka pratham samooh hai aur in sabki sanyojakata bhi haaidrojan, kloreen tatha oksijn sab ke prati ek hoti hai. isi prakaar dviteeya (maigneeshiym, kailsiym aadi), truteeya (boraun, ailyoominiym aadi) tatha chaturth (kaarban, silikn aadi) samooh ke tatvon ki sanyojakata kramash: do, teen tatha chaar hai. paaainchavein (naaitrojan, fausaforas aadi), chhathe (salfr, kromiym aadi), saatavein (fluoreen, kloreen, bromeen aadi) samooh ke tatv okseejan ke prati to kramash: paaainch, chhah tatha saat sanyojakataaeain pradarshit karte hain, parantu haaidrojan tatha kloreen ke prati in samoohon ke tatvon ki sanyojakataaeain kramash: teen, do tatha ek hain.

raasaayanik bandh

20veen shataabdi ke aaranbhik kaal mein vaigyaanik sar J.J. taumasan tatha neels bor ne prayogon tatha apni kalpanaaon dvaara paramaanuon ki rachana ke baare mein hamaare gyaan mein vruddhi ki or radarafard ne paramaanuon ke naabhik (nuclear) roop ki vivechana ki. iske anusaar pratyek parmaanu ke kendra ya naabhi mein bahut sookshm pind hota hai, jispar dhanaavesh hota hai aur isi dhanaavesh ki baraabar sankhya ke ilaiktraun (electron) kendra ke chaaron or paridhiyon mein chakkar lagaaya karte hain. antim paridhi ke ilektraunon ko 'sanyojan ilektraun' ka naam diya gaya hai, kyonki 'sanyojakata ke ilektraun siddhaant' ke anusaar, yahi ilektraun tatv ki sanyojanashakti nirdhaarit karte hain. udaaharan ke liye, aavart taalika ke pratham do samoohon ke paramaanuon ki rachana neeche di gayi hai :

 H He

 1 2

Li Be B C N O F Ne

2,1 2,2 2,3 2,4 2,5 2,6 2,7 2,8

Na Mg Al Si P S Cl Ar

2,8,1 2,8,2 2,8,3 2,8,4 2,8,5 2,8,6 2,8,7 2,8,8

uparyukt saarani mein nishkriya gaison ke paramaanuon ki antim paridhi mein (heeliym ko chhodkar jismein 2 ilektraun hote hain) 8 ilektraun hote hain. aisa prateet hota hai ki yeh vinyaas itna sthaayi hai ki ye swayam saadhaaranataya kisi raasaayanik kriya mein bhaag naheen lete aur anya tatv bhi ek, do, ya teen ilektraun khokar, ya badhaakar, inheen ke vinyaas ko praapt karne ki cheshta karte hain. udaaharan ke liye, sodiym ka parmaanu ek ilektraun khokar aur fluoreen ka parmaanu ek ilektraun ki vruddhi karke sodiym floraaid banaate hain aur is kriya mein sodiym (Na+) tatha fluoraaid donon aayan nishkriya gas neeon ka ilektraun vinyaas praapt kar lete hain. is prakaar ki sanyojakata ko vidyut sanyojakata (electrovalency) kaha jaata hai.

vidyutsanyojakata se bane yaugik saadhaaranataya uchch galanaank aur kvathanaankavaale hote hai aur jal mein vileen hokar aayanit ho jaate hain. is prakaar ki vidyutsanyojakata ki kalpana sarvapratham jarman rasaayanajnya kausel (Kossel) ne 1916 mein ki thi. iske atirikt Amreeki rasaayanajnya lyoois (Lewis) ne kuchh hi maas baad kalpana ki ki uparyukt vidhi ke atirikt kuchh tatv ek anya vidhi se bhi nishkriya gaison ka ilektraun vinyaas praapt kar sakte hain. is kalpana ke anusaar sanyog karanevaale do parmaanu kabhi kabhi apne ek, do, ya teen ilektraunon ka saajha karke donon ke donon nishkriya gaison ka vinyaas praapt kar lete hain. is prakaar ki sanyojakata ko sahasanyojakata (covalency) ka naam diya gaya hai aur ismein bane sahasanyojak yaugik saadhaaranataya nimn galanaank tatha kvathanaank pradarshit karte hai aur adhiktar kaarbanik vilaayakon mein vileya hote hain.

in donon ke atirikt ek anya prakaar ki sanyojakata ki kalpana ki gayi hai, jismein ek yaugik ya tattv apne do khaali ilektraun kisi doosare yaugik ya tatv ko dekar, donon mein nishkriya gaison ke ilektraun vinyaas ki avastha la deta hai. udaaharan ke liye, amoniya apne do khaali ilaiktraun haaidrojan ya boraun kloraaid ko pradaan karke, unako kramash: heeliym tatha neeon ka ilaiktraun vinyaas de deta hai. is prakaar ki sanyojakata ko upasahasanyojakata (Coordinate covaiency) kaha gaya hai, kyonki is prakaar ki sanyojakata ki kalpana upasahasanyojak yaugikon, jaise heksaaaimeen, kobaalti kloraaid tatha potaishiym ferosaayanaaid aadi ke gunon ko samajhne mein bahut sahaayak siddh hui hai.

naamakaran tatha tatvon ki sanyojakata ka vitran

tatvon ki aavart saarani, jo unke elektraanik vinyaas par aadhaarit hai, kisi tatv ke parmaanu me sabse baahari kaksha me upasthit ilektraano ki sankhya hi us tatv ki sanyojakata hoti hain. tatvon ki sanyojakata ka ek sanket deti hai:

  • sanyojakata 0 :
    • sanyojakata 0: He, Ne, Ar, Kr, Xe, Rn
  • sanyojakata 1 : ekasanyoji
    • Valence 1: H, Li, Na, K, Rb, Cs, Fr, Ag, Cu, Hg, Au, F, I, Br, Cl
  • sanyojakata 2 : dvisanyoji
    • Valence 2: Be, Mg, Ca, Sr, Ba, Ra, Fe, Ni, Cu, Zn, Cd, Pt, Hg, Sn, Pb, O, Si, Se, Te, C, Po
  • sanyojakata 3 : trisanyoji
    • Valence 3: Al, Au, Fe, Co, Ni, Cr, Mn, Cl, Br, I, Ga, In, Tl, N, P, As, Sb, Bi, Cr
  • sanyojakata 4 : chatu:sanyoji
    • Valence 4: C, Si, Ge, Sn, Pb, S, Se, Te, Pt, Ir, Mn, S, N, Po
  • sanyojakata 5 : panchasanyoji
    • Valence 5: Bi, Sb, As, P, N, I, Br, Cl
  • sanyojakata 6 : shatasanyoji
    • Valence 6: Te, Se, S, Mn, Cr
  • sanyojakata 7 : saptasanyoji
    • Valence 7: Mn, Cl, Br, I
  • sanyojakata 8 : ashtasanyoji

sandarbh

inhein bhi dekhein

  • raasaayanik aabandh