Tsimikizani ndi valence wa zinthu mankhwala a

Chidziwitso cha kapangidwe ka atomu ndi mamolekyulu m'zaka za m'ma XIX sindingakhoze kufotokoza chifukwa chimene ena chiwerengero cha maatomu kupanga kumangidwa ndi particles ena. Koma malingaliro a asayansi pasadakhale awo, ndi valence likupitirizabe akuphunziridwa monga mmodzi wa mfundo zimapangidwira.

Mbiri ya lingaliro la "valence wa zinthu mankhwala"

Apadera British sayansi XIX m'ma Edvard Franklend anayambitsa mawu akuti "kulankhulana" mu ntchito ya sayansi pofotokoza mogwirizana kwa maatomu ndi mzake. Scientific anaona kuti zinthu mankhwala kupanga mankhwala ndi yofanana maatomu ena. Mwachitsanzo, asafe amamangirira maatomu wa hydrogen atatu molekyulu wa ammonia.

Mu May 1852 Frankland kuika patsogolo pa amanena kuti pali nambala yeniyeni kumangidwa mankhwala kuti atomu akhoza kupanga ndi particles tina ting'onoting'ono ta pa nkhaniyi. Frankland anagwiritsa ntchito mawu akuti "mphamvu polumikiza" pofotokoza zomwe kenako adzatchedwa valence. zamankhwala British oikidwa monga nsinga mankhwala kupanga ma atomu a zinthu payekha wodziwika mu zaka za m'ma XIX. Ntchito Frankland anali Athandiza Kwambiri umagwirira ano structural.

chitukuko cha maganizo

German sayansi FA Kekule anatsimikizira mu 1857 kuti mpweya ndi chetyrehosnovnym. Mu losavuta ake pawiri - dziko - uka chifukwa 4 maatomu wa hydrogen. Mawu akuti "basicity" wasayansi ntchito udindo zinthu katundu kulumikiza nambala atathana ndi tinthu ena. Mu Russia, deta pa kapangidwe ka nkhani systematized A. M. Butlerov (1861). Komanso chitukuko cha chiphunzitso cha mankhwala chomangira timapemphera ziphunzitso za kusintha nthawi ndi katundu wa zinthu. Mlembi wake - china chapadera Russian sayansi D. I. Mendeleev. Inatsimikizira kuti valence mbali mankhwala mankhwala, ndi zina ofunitsitsa ndi malo amene iwo akukhala dongosolo nthawi.

Mawonekedwe chifaniziro cha valence ndi mankhwala kogwirizana

Kutheka Kuona mamolekyulu - mmodzi wa nyota undoubted chiphunzitso valence. Chitsanzo choyamba anaonekera mu 1860, ndipo kuyambira 1864 wakhala akugwiritsa ntchito mitunduyi structural woimira mankhwala circumferential chizindikiro mkati. Pakati zizindikiro mukapeza ma atomu amaimira mankhwala akapolo, ndi chiwerengero cha mizere ndi wofanana valence lapansi. Mu zaka zomwezo, anapangidwa choyamba sharosterzhnevye chitsanzo (onani. Photo kumanzere). Mu 1866 Kekule akufuna chitsanzo stereochemical maatomu mpweya mu mawonekedwe a tetrahedron, amene anaphatikizapo mu buku lake "Organic Chemistry".

Valence wa zinthu mankhwala, ndi zikamera wa ubale kuphunzira ndi G. Lewis, amene lofalitsidwa ntchito zake mu 1923 pambuyo anapeza elekitironi lapansi. Chotero anaitana zoipa mlandu particles kakang'ono, zomwe zili mbali ya zipolopolo atomiki. Mu buku lake, Lewis ntchito mfundo kuzungulira mbali zonse zinayi za chizindikiro mankhwala kwa kuwonetsera kwa ma elekitironi valence.

Valency wa hydrogen ndi mpweya

Asanalengedwe dongosolo nthawi ya valence mbali mankhwala mankhwala linapangidwa kuyerekeza ndi ma atomu amene amadziwika. Hydrogen ndi mpweya anasankhidwa buku. Chinthu china mankhwala umalakalaka kapena mmalo nambala inayake ya H maatomu, ndi O.

Mu njira iyi, katundu anali otsimikiza mankhwala ndi monovalent ndi wa hydrogen (a valency wa chinthu chachiwiri zinaperekedwa mwa numeral Chiroma):

• HCl - chloro (I):
• H ₂ O - mpweya (II);
• NH ₃ - asafe (III);
• CH ₄ - mpweya (IV).

The oxides a K ₂ O, NKHA, N ₂ O _3, SiO _{2, 3} anatsimikiza ndi valence zitsulo ndi nonmetals mpweya, anawaonjezera kuwirikiza kawiri chiwerengero cha maatomu attachable O. analandira zotsatirazi makhalidwe: K (I), C ( II), N (III) , Si (IV), S (VI).

Kodi kudziwa valence wa zinthu mankhwala a

Pali malamulo mapangidwe kumangidwa mankhwala ndi elekitironi awiriawiri wamba:

• Chitsanzo wa hydrogen valence - I.
• Normal mpweya valence wa - II.
• Pakuti zinthu nonmetals-m'munsi valence zingadziŵike mwa chilinganizo 8 - № gulu limene ali mu dongosolo nthawi. Apamwamba, ngati zingadziŵike ndi nambala gulu.
• Pakuti zinthu mbali ya subgroups pazipita zotheka valency ndi chimodzimodzi chiwerengero cha magulu tebulo nthawi.

Khama la valence wa zinthu mankhwala pawiri wa chilinganizo ikuchitika ntchito aligorivimu zotsatirazi:

1. Lembani pamwamba pa mankhwala bwino kudziwika kufunika kwa mbali. Mwachitsanzo, MN ₂ O ₇ mpweya valency ndi II.
2. Kuwerengera phindu okwana zimene ziyenera kuchulukitsa ndi valence chiwerengero cha maatomu a yemweyo mankhwala amafotokozera mu molekyulu; 2 * 7 = 14.
3. Kudziwa valency wa chinthu chachiwiri, chomwe ndi losadziwika. Gawani zopezera Dec. 2 mtengo ndi nambala ya MN maatomu mu molekyulu ndi.
4. 14: 2 = 7. valence wa okusayidi manganese mu apamwamba ake - VII.

Permanent ndi variable valency

Valence makhalidwe a hydrogen ndi mpweya ndi osiyana. Mwachitsanzo, sulfa m'magawo pawiri wa H ₂ S ndi divalent, monga mwa chilinganizo CHONCHO ₃ - hexavalent. The mpweya monoxide amachitira ndi mpweya, NKHA ndi NKHA ₂ woipa. Pawiri choyamba ndi valence wa C II, ndipo lachiwiri - IV. Mtengo chomwecho mu dziko CH _4.

Ambiri mwa zinthu alibe kuonetsa zonse ndi variable valence, mwachitsanzo, phosphorous, asafe, sulfure. Kufunafuna zimayambitsa zikuluzikulu za zodabwitsazi zinachititsa kuti chiphunzitso cha mankhwala kogwirizana, mfundo za ma elekitironi valence chipolopolo, orbitals maselo. Kupezeka kwa mfundo zosiyanasiyana za katundu yemweyo analandira ndi malongosoledwe a kapangidwe ka atomu ndi mamolekyulu malo.

malingaliro amakono a valence

maatomu onse lapangidwa ndi phata zabwino atazunguliridwa ndi ma elekitironi zoipa mlandu. Chipolopolo kunja, zomwe iwo amapanga, ndi yosatha. Kapangidwe anamaliza ndi khola kwambiri, lili 8 ma elekitironi (octet). Chemical kogwirizana ndi wamba zotsatira elekitironi awiriawiri mu chikhalidwe maatomu ankafalitsa mwakhama yabwino.

Rule mapangidwe mankhwala ndi kumalizidwa kwa chipolopolo kapena kulandira ma elekitironi angadzachite unpaired - malingana ngati ndondomeko ndi kosavuta pochitika. Ngati atomu amapereka mapangidwe mankhwala chomangira particles zoipa opanda nsapato, nsinga ndipamene bola unpaired ma elekitironi. Malinga ndi mfundo ano, valence ma atomu a zinthu mankhwala - ndi kubereka nambala inayake kumangidwa covalent. Mwachitsanzo, mu molekyulu, ndi H ₂ S sulfure, sulfide wa hydrogen amapeza valence II (-), chifukwa aliyense atomu nawo mu mapangidwe mitundu iwiri iwiri elekitironi. Chizindikiro "-" akusonyeza kukopa kwa awiri elekitironi kuti zinthu zambiri electronegative. Osachepera electronegative kufunika valence appends "+".

Pamene limagwirira mwiniwake-acceptor zimakhudzidwa ndondomeko elekitironi awiriawiri chinthu china ndi zina ufulu valence orbitals.

The kudalira wa valence ya kapangidwe ka maatomu

Taganizirani mwachitsanzo carbon ndi oxygen, monga izo zimatengera kapangidwe ka zinthu valence wa zinthu mankhwala a. Zodziwitsa Table apereka mwachidule makhalidwe zoyambirira za mpweya atomu:

• chizindikiro mankhwala - C;
• item chiwerengero - 6;
• nyukiliya mlandu - 6;
• mapulotoni mu phata - 6;
• elekitironi - 6, kuphatikizapo 4 kunja, 2 umene kupanga nsapato, 2 - unpaired.

Ngati mpweya atomu ndipamene maunyolo awiri monoookside NKHA, ndiye ntchito umaperekedwa 6 okha particles negative. Kuti tikhale octets anafunika awiriwiri ndi mnyamata 4 anapanga kunja particles negative. Mpweya ali valence wa IV (+) mu woipa ndi IV (-) mu dziko.

Ordinal chiwerengero cha mpweya - 8, valence chipolopolo tichipeza ma elekitironi asanu, awiri a iwo kupanga awiri ndi zimakhudzidwa nsinga mankhwala ndipo mogwirizana ndi maatomu ena. Chitsanzo mpweya valence - II (-).

The valency ndi makutidwe ndi okosijeni boma

Nthawi zambiri yabwino kwambiri kugwiritsa ntchito mawu akuti "mlingo wa makutidwe ndi okosijeni". Chotero anaitana mlandu atomu umene kuti tikhale ngati ma elekitironi onse asamukira amafotokozera kumanga lomwe lili ndi phindu elektroootritsatelnosti apamwamba (EO). The makutidwe ndi okosijeni chiwerengero wa chinthu chophweka ndi ziro. Ndi makutidwe ndi okosijeni kwambiri EO anawonjezera amafotokozera "-" chizindikiro, kupatula electronegative - "+". Mwachitsanzo, waukulu gulu zitsulo makutidwe ndi okosijeni lililonse ndi ion anapatsa chiwerengero wofanana ndi chizindikiro cha "+". Nthawi zambiri valency ndi makutidwe ndi okosijeni boma la atomu mu pawiri chomwecho numerically mwamalunji. Only pamene mogwirizana ndi maatomu enanso electronegative zabwino makutidwe ndi okosijeni boma, ndi zinthu lake EO pansipa - negative. Lingaliro la "valence wa" Nthawi zambiri amangonena za thunthu la dongosolo la maselo.