Moolasha, culeyska molarka iyo tirada Avogadro

Tirinta walxaha iyadoo la miisaamayo

Atamyadu aad bay u yar yihiin in mid-mid la tiriyo, sidaa darteed kimistariyaashu waxay u tiriyaan koox go'an, sida dukaanku u tiriyo ukunta tobanle-tobanle. Kooxdaasi waa moolka. Tan iyo dib-u-eegista SI ee 2019, hal mool wuxuu ka kooban yahay si sax ah 6.02214076 × 10²³ walxood oo la cayimay, joogtada Avogadro-na waxaa lagu qeexay si sax ah 6.02214076 × 10²³ mol⁻¹. Xisaabaha, 6.022 × 10²³ mol⁻¹ badanaa way ku filan tahay.

Walaxda had iyo jeer waa in la sheegaa. Hal mool oo atamyada oksijiinta (O) ah iyo hal mool oo molekiyuullada oksijiinta (O₂) ah waxay ka kooban yihiin isla tirada walxo, laakiin kan labaad wuxuu leeyahay laba jibaar atamyo oo culeys laba jibaar ah. Qorista qaacidada qaddar kasta agtiisa, sida 0.50 mol O₂, waxay ka hortagtaa wax badan oo isku-qaldan oo ardaydu kula kulmaan moolasha.

Sababta garaam mool kasta u waafaqsan yahay culeyska qaacidada

Culeyska atamka caadiga ah ee curiye waa celcelis aan cutub lahayn oo culeysyada isotoobyadiisa ah, oo lagu miisaamay tirada dabiiciga ah una muuqda marka loo eego hal-iyo-toban meelood meel culeyska atam carbon-12. Moolka waxaa markii hore la qeexay si hal mool walax ah uu u leeyahay culeys garaam ah oo tiro ahaan le'eg culeyska atamkeeda ama qaacidadeeda. Tan iyo dib-u-qeexidda 2019, isku-waafaqsanaantaasi mar dambe sax ma aha qeexid ahaan, laakiin weli waxay jirtaa ilaa hal qayb boqolaal malyuun. Culeyska atamka chlorine waa qiyaastii 35.45, sidaa darteed culeyskiisa molarka waa 35.45 g/mol, in kasta oo atam chlorine ah oo keliya aanu lahayn culeyskaas; chlorine dhabta ahi waa isku-darka chlorine-35 iyo chlorine-37.

Hagahan wuxuu isticmaalaa culeysyada atamka caadiga ah ee IUPAC oo loo dhoweeyey laba meelood oo tobanle: H 1.01, C 12.01, N 14.01, O 16.00, Al 26.98 iyo S 32.06. Si aad u hesho culeyska molarka ee isku-dhis, ku dar culeysyada atamka ee atam kasta oo ku jira qaacidada, adigoo mid walba ku dhufanaya hoos-tirooyinkiisa iyo isku-dhufte kasta oo ka baxsan qaansooyinka.

Aluminum sulfate, Al₂(SO₄)₃, qaansooyinku waxay ka dhigan yihiin saddex kooxood oo sulfate ah. Cutubka qaacidadu sidaa darteed wuxuu ka kooban yahay 2 Al, 3 S iyo 12 O: 2(26.98) + 3(32.06) + 12(16.00) = 53.96 + 96.18 + 192.00 = 342.14 g/mol.

Khariidadda garaamka, moolasha iyo walxaha

Dhibaato kasta oo mawduucan ah waa waddo saddex sanduuq dhex mara: culeys garaam ah, qadar mool ah iyo tirada walxaha. Culeyska molarku wuxuu isku xidhaa labada ugu horreeya; joogtada Avogadro waxay isku xidhaa labada ugu dambeeya. Moolasha waa meesha dhexe had iyo jeer. Ma jirto beddel toos ah oo garaam ka gudba walxaha oo moolka ka bood.

Sanduuqa walxaha gudahiisa waxaa ku jira hal tallaabo oo dheeraad ah. Qaacidadu waxay kuu sheegaysaa immisa atam ama ayoon oo nooc kasta ah ayaa ku jira hal molekiyuul ama hal cutub qaacido, hoos-tirooyinkaasna waa arrimo tirin oo sax ah.

• Garaam ilaa mool: ku qaybi culeyska molarka (ku dhufo 1 mol / M g).
• Mool ilaa garaam: ku dhufo culeyska molarka.
• Mool ilaa walxo: ku dhufo 6.022 × 10²³ mool kasta.
• Walxo ilaa mool: ku qaybi 6.022 × 10²³ mool kasta.
• Molekiyuullo ama cutubyo qaacido ilaa atamyo ama ayoonno: ku dhufo hoos-tirada atamkaas ama ayoonkaas.

Tusaale la xaliyey: laga bilaabo milligram kafeyn ilaa atamyada nitrogen

Muunad kafeyn ah, C₈H₁₀N₄O₂, culeyskeedu waa 95.0 mg. Immisa molekiyuul kafeyn ah iyo immisa atam nitrogen ah ayay ka kooban tahay?

Tallaabo 1, culeyska molarka: 8(12.01) + 10(1.01) + 4(14.01) + 2(16.00) = 96.08 + 10.10 + 56.04 + 32.00 = 194.22 g/mol. Tallaabo 2, culeyska u beddel garaam, kadibna mool: 95.0 mg × (10⁻³ g / 1 mg) = 0.0950 g, iyo 0.0950 g × (1 mol / 194.22 g) = 4.8914 × 10⁻⁴ mol. Hadda ilaali tirooyinka dheeraadka ah.

Tallaabo 3, mool ilaa molekiyuullo: 4.8914 × 10⁻⁴ mol × 6.022 × 10²³ molekiyuul/mol = 2.9456 × 10²⁰, oo loo sheego 2.95 × 10²⁰ molekiyuul. Tallaabo 4, molekiyuul kastaa wuxuu leeyahay afar atam nitrogen ah, tiro sax ah: 2.9456 × 10²⁰ × 4 = 1.18 × 10²¹ atam nitrogen ah. Culeyska 95.0 mg wuxuu leeyahay saddex tiro oo muhiim ah, sidaa darteed labada jawaabba sidoo kale.

Hubi cabbirka: toban meelood meel garaam waa qayb yar oo mool ah walax culeyskeeda molarka uu yahay qiyaastii 200 g/mol, sidaa darteed qadarku waa inuu noqdaa qiyaastii 0.1 ÷ 200 = 5 × 10⁻⁴ mol, tirada molekiyuulladuna waa inay aad uga hooseeyaan 10²³. Labada hubinba waa gudbeen.

Tusaale la xaliyey: laga bilaabo tirada cutubyada qaacidada ilaa dib garaam

Muunad aluminum sulfate ah waxay ka kooban tahay 3.15 × 10²² cutubyo qaacido ah. Waa maxay culeyskeeda, iyo immisa ayoon sulfate ah iyo atam oksijiin ah ayay ka kooban tahay?

Tallaabo 1, walxo ilaa mool: 3.15 × 10²² ÷ 6.022 × 10²³ mol⁻¹ = 0.052308 mol. Tallaabo 2, mool ilaa garaam iyadoo la isticmaalayo culeyska molarka ee hore loo helay: 0.052308 mol × 342.14 g/mol = 17.897 g, oo loo sheego 17.9 g.

Tallaabo 3, u isticmaal qaacidada sida qalab tirin. Cutub qaacido Al₂(SO₄)₃ kastaa wuxuu ka kooban yahay saddex ayoon sulfate ah, SO₄²⁻, sidaa darteed muunaddu waxay haysaa 3 × 3.15 × 10²² = 9.45 × 10²² ayoon sulfate ah. Cutub qaacido kastaa wuxuu leeyahay 12 atam oksijiin ah, sidaa darteed muunaddu waxay haysaa 12 × 3.15 × 10²² = 3.78 × 10²³ atam oksijiin ah, wax yar ka badan badh mool oo atamyo oksijiin ah. Isku-dhisyada ayoonka ah waxay ka kooban yihiin cutubyo qaacido halkii ay ka ahaan lahaayeen molekiyuullo, laakiin macquulnimada tirintu waa isku mid.

Khaladaadka moolka ee ka yimaada lumitaanka walaxda

Khaladaad badan oo moolasha ahi ma aha khaladaad xisaabeed. Waxay ka yimaadaan ilaawidda waxa la tirinayo ama isticmaalka arrin jiho khaldan. Qiyaas degdeg ah kahor xisaabinta ayaa qabata intooda badan.

Qor qaddar kasta oo leh cutubkiisa iyo walaxdiisa, sida 0.0523 mol Al₂(SO₄)₃ ama 9.45 × 10²² ayoon SO₄²⁻, oo magacaw fallaarta ku jirta khariidadda garaamka, moolasha iyo walxaha ee tallaabo kasta raacayso. Tallaabo aan fallaar la mid ahayn badanaa waa khaladka.

• Isku-qaldidda atamyada iyo molekiyuullada: 1.0 mol oo O₂ ah culeyskeedu waa 32.00 g, ma aha 16.00 g, waxayna ka kooban tahay 2.0 mol atamyo O ah.
• Iska indha-tirka isku-dhufte ka baxsan qaansooyinka: Al₂(SO₄)₃ waxaa ku jira 12 atam oksijiin ah cutub qaacido kasta, ma aha 4.
• Ku dhufashada joogtada Avogadro marka walxaha loo beddelayo mool: qadar mool ah oo muunad shaybaar oo caadi ahi waa inuu noqdaa lambar dhexdhexaad ah, ma aha mid ku dhow 10²³ ama ka sarreeya.
• Isticmaalka lambarka culeyska halkii culeyska atamka: chlorine waa 35.45 g/mol, ma aha 35 ama 37.
• Ka boodidda moolka: garaamka toos looma beddeli karo walxo ama garaam walax kale.
• Dhoweynta culeyska molarka ama qadarrada dhexe goor hore, taasoo beddeli karta tirada ugu dambeysa ee la sheegay.