Me yasa Ma'adanai ke da wasu siffofi na lu'ulu'u?
Idan kun taɓa ganin quartz mai siffar prism, gishirin tebur wanda yake kama da ƙananan cubes, ko pyrite, wanda galibi yake kama da daskararren zinare, kuna iya mamakin: me yasa ma'adanai ke da wasu siffofi na lu'ulu'u? Kyawun siffofi na ma'adinai ba haɗari bane. Su "alamu" ne na yadda aka tsara atom ɗin ma'adinan da kuma yadda ma'adinan ke girma a yanayi. Wannan labarin zai tattauna dalilan kimiyya da ke bayan siffofin lu'ulu'u na ma'adinai, daga tsarin atomic, hanyoyin samarwa , zuwa abubuwan muhalli da ke shafar siffarsu ta ƙarshe.
1. Ma'adanai da lu'ulu'u: menene alaƙar?
Ma'adanai abubuwa ne da ke faruwa a zahiri (wanda aka samar ba tare da taimakon ɗan adam ba), gabaɗaya ba su da wani sinadari na halitta, tare da takamaiman sinadari da kuma tsarin ciki na yau da kullun. Wannan tsarin ciki na yau da kullun ana kiransa tsarin lu'ulu'u. Saboda haka, idan muka ce ma'adinai "lu'ulu'u ne," ba wai kawai muna nufin siffar waje ta kusurwa ba, amma a'a, an tsara ƙwayoyin halittarsa cikin tsari mai maimaitawa.
Siffar waje ta lu'ulu'u (wanda ake kira al'adar lu'ulu'u) tana nuna tsarin ciki, kodayake ba koyaushe yake cikakke ba saboda yanayin samuwar yana shafar sa.
2. Babban dalili: tsarin ƙwayoyin halitta a cikin layin lu'ulu'u
A matakin ƙananan ƙwayoyin halitta, ana shirya ƙwayoyin halitta a cikin ma'adanai a cikin tsari mai maimaitawa mai girma uku, wanda ake kira lattice na lu'ulu'u. Wannan tsari ana ƙaddara shi ta hanyar:
– Girman da kuma nauyin ions/atom ɗin da ke cikinsa
- Nau'in haɗin sinadarai (ionic, covalent, ƙarfe, ko gauraye)
– Yadda ƙananan raka'a (misali silicate tetrahedrons) ke maimaitawa don samar da manyan gine-gine
Saboda tsarin cikin su na yau da kullun ne, girman ma'adinai shi ma yana faruwa akai-akai. Wannan yana haifar da bayyanar saman da ba su da matsala (fuskoki) da wasu kusurwoyi. Wannan shine dalilin da yasa quartz yakan samar da prisms mai siffar hexagonal, yayin da halite (NaCl) yakan samar da cubes.
Misali mai sauƙi
– Halite (gishirin dutse, NaCl): An shirya ions na Na⁺ da Cl⁻ a cikin tsarin cubic. Lokacin girma, siffar da ta fi dacewa da wannan tsari ita ce cubic.
– Quartz (SiO₂): tsarin silica tetrahedrons yana samar da daidaiton hexagonal, don haka siffar waje sau da yawa tana kama da prism mai gefe shida tare da ƙarshen pyramidal.
3. Daidaiton lu'ulu'u da "dokokin" daidaiton tsari
Lu'ulu'u suna nuna daidaito, wanda shine maimaita tsari iri ɗaya idan aka juya shi ko aka yi masa madubi a wani takamaiman alkibla. Wannan daidaiton yana raba lu'ulu'u zuwa tsarin lu'ulu'u. Gabaɗaya, akwai manyan tsarin lu'ulu'u guda bakwai:
1. Cubic (isometric)
2. Tetragonal
3. Orthorhombic
4. Mai siffar murabba'i
5. Trigonal
6. Asibitin Monoclinic
7. Triclin
Kowace tsarin tana da ƙa'idodi na musamman don kusurwoyi da tsayin axis. Saboda haka, ma'adanai a cikin tsarin iri ɗaya galibi suna nuna halaye iri ɗaya na siffa. Misali, ma'adanai a cikin tsarin cubic suna nuna siffofi na cubic, octahedron, ko dodecahedron.
4. Me yasa wasu yankuna suka fi rinjaye?
Duk da cewa layin lu'ulu'u yana samar da "tsari na asali," ana ƙayyade siffar ƙarshe ta wacce jiragen sama suka fi karko a cikin kuzari. A cikin girman lu'ulu'u:
- Jiragen sama masu ƙarancin kuzarin saman suna dawwama kuma suna bayyana kamar saman lu'ulu'u.
- Filaye masu ƙarfin makamashin saman suna girma da sauri kuma daga ƙarshe suna "ɓacewa" daga siffar waje.
A wata ma'anar, lu'ulu'u za su "zaɓi" siffar da ke rage ƙarfin kuzari gaba ɗaya. Wannan ƙa'ida tana taimakawa wajen bayyana dalilin da yasa ma'adinan iri ɗaya zai iya samun siffofi iri-iri yayin da har yanzu yake bin wasu iyakokin daidaito.
5. Yanayin girma: sarari, lokaci, da kuma samar da kayan aiki
Siffar lu'ulu'u tana da tasiri sosai a yanayin da ma'adinan ke samuwa. Wasu daga cikin muhimman abubuwan sune:
a) Dakin girma
Idan ma'adinai yana da sarari mara komai (misali ramuka a cikin duwatsun aman wuta (ko geodes), lu'ulu'u na iya girma cikin 'yanci kuma su samar da fuskoki daban-daban na lu'ulu'u. Duk da haka, idan suka girma a cikin wani wuri mai iyaka, lu'ulu'u suna taruwa a junansu kuma suna zama ba su da tsari.
Misali:
- Lu'ulu'u na quartz a cikin ƙasa galibi suna da kaifi da haske.
– Quartz a cikin duwatsu masu ƙarfi na iya zama babban lu'ulu'u ba tare da siffar prism bayyananne ba.
b) Saurin sanyaya ko samar da iska
– Sanyaya a hankali (misali a cikin kutsewar magma) yana ba da damar atoms su kasance cikin tsari mai kyau → manyan lu'ulu'u da ƙarin siffofi na yau da kullun.
– Sanyaya da sauri (misali lava a saman) yana sa ƙwayoyin halitta su “kulle” kafin su zama masu tsari → ƙananan lu'ulu'u ko ma gilashin aman wuta (ba tare da lu'ulu'u ba).
c) Tattarawa da samar da sinadaran
Idan abubuwan da ke cikinsa sun yi yawa kuma sun yi karko, lu'ulu'u za su iya girma daidai. Idan wadatar ta canza, girma ba ta daidaita ba, wanda ke haifar da nakasa ko siffofi masu layi-layi.
6. Zafin jiki, matsin lamba, da kuma rawar da ruwa/maganin ke takawa
Ma'adanai da yawa suna girma daga ruwan zafi (ruwa mai zafi, mai wadataccen ma'adinai) ko kuma daga canjin yanayi (canjin dutse saboda yanayin zafi da matsin lamba). Zafin jiki da matsin lamba suna shafar ma'adanai ta hanyoyi da dama:
– Ka tantance waɗanne ma'adanai ne suka tabbata (wasu ma'adanai suna bayyana ne kawai a ƙarƙashin wasu yanayi).
– Yana canza saurin yaduwar kwayar halitta ta atomic, ta haka yana shafar girma da ingancin lu'ulu'u.
- Yana shafar narkewar abinci: ma'adinan ma'adinai idan yanayi ya canza (misali maganin ya yi sanyi ko kuma matsin lamba ya ragu).
Ruwa kuma zai iya hanzarta tsarin samuwar lu'ulu'u domin yana sauƙaƙa wa ions su motsa su taru don samar da layi.
7. Najasa da lahani na lu'ulu'u: siffa na iya canzawa
Ma'adanai ba sa cika tsarkakewa 100%. Sauran ions na iya shiga layin lu'ulu'u a matsayin maye gurbin wasu ƙwayoyin zarra (maye gurbinsu). Waɗannan ƙazanta na iya:
– Canza launi (misali amethyst: purple quartz saboda tasirin abubuwan da aka gano da kuma hasken rana).
– Canza yadda lu'ulu'u ke girma ta yadda siffarsu ba ta "dace ba".
– Yana haifar da lahani (ɓacewa) wanda ke shafar sheƙi da tauri.
Ko da akwai lahani, tsarin asali har yanzu yana bin ƙa'idodin rubutun kristal, don haka har yanzu ana iya gane siffar gabaɗaya.
8. Haɗawa da haɗakarwa: lu'ulu'u suna kama da "abin mamaki" amma har yanzu suna da yawa.
Wani lokaci lu'ulu'u biyu ko fiye suna girma a haɗe da juna a cikin takamaiman tsari na yau da kullun. Wannan ana kiransa lu'ulu'u tagwaye. Tagwaye na iya samar da siffofi na musamman waɗanda suka yi kama da masu rikitarwa amma a zahiri suna bin ƙa'idodin daidaito.
Bugu da ƙari, ma'adanai sau da yawa suna girma a matsayin tarawa: tarin ƙananan lu'ulu'u da yawa. A cikin tarawa, siffar lu'ulu'u ɗaya yana da wuyar ganewa, amma har yanzu akwai daidaito a sikelin ƙananan.
9. Me yasa ma'adinan iri ɗaya zai iya samun siffofi daban-daban?
Za mu iya samun ma'adinan iri ɗaya amma siffarsa ta bambanta. Wannan yana faruwa ne saboda:
- Yanayi daban-daban na girma (zafin jiki, matsin lamba, mafita, sarari)
- Bambance-bambance a cikin ƙimar girma a wasu hanyoyi
– Kasancewar ƙazanta ko wasu ma'adanai da ke hana girma
- Tsarin yanayi ko yashewa wanda ke canza saman lu'ulu'u
Duk da haka, ko da siffar waje na iya canzawa, kusurwoyin da ke tsakanin jiragen lu'ulu'u a cikin ma'adinan iri ɗaya suna dawwama a koyaushe. A cikin tsarin lu'ulu'u na gargajiya, an san wannan a matsayin ƙa'idar cewa kusurwoyin da ke tsakanin jiragen sama a cikin wani lu'ulu'u na ma'adinai suna dawwama, saboda sun samo asali ne daga tsarin ciki ɗaya.
Kammalawa
Ma'adanai suna da takamaiman siffofi na lu'ulu'u musamman saboda tsarin ƙwayoyin halitta na yau da kullun a cikin layin lu'ulu'u da kuma daidaiton tsarinsu na ciki. Siffar waje da muke gani sakamakon hulɗar da ke tsakanin wannan "tsari" na ciki da abubuwan muhalli kamar sararin girma, zafin jiki, matsin lamba, ƙimar samuwar, da kuma tsarin mafita da ƙazanta. Saboda haka, lu'ulu'u na ma'adinai haɗuwa ne na dokokin kimiyyar lissafi da sunadarai na yau da kullun a matakin atom da kuma yanayin yanayi a lokacin samuwarsu.
Siffofin lu'ulu'u ba wai kawai suna da kyau a tattara su ba, har ma suna da mahimmanci ga kimiyya: daga siffar lu'ulu'u da tsarinsu, masana ilmin ƙasa za su iya fahimtar yanayin da duwatsu suka samo asali a ƙarƙashinsu, tarihin ilimin ƙasa, har ma da albarkatun ma'adinai na wani yanki. Ta hanyar fahimtar dalilin da yasa ma'adanai ke da wasu siffofi, muna karanta "rikodin" hanyoyin halitta da aka adana a cikin tsarin atom.
