Peb txhua tus tau hla cov ntsiab lus ntawm kev tshawb fawb xws li chemistry. Qee lub sij hawm lawv zoo ib yam li nws nyuaj rau kev paub qhov txawv ntawm ib leeg. Tab sis nws yog ib qho tseem ceeb heev kom to taub tag nrho cov ntawm lawv, vim hais tias tej lub sij hawm xws li kev nkag siab yuam kev ua rau cov xwm txheej ruam heev, thiab qee zaum ua yuam kev tsis tuaj yeem zam txim. Hauv tsab xov xwm no peb yuav qhia koj tias dab tsi hydrides yog dab tsi, qhov twg yog qhov txaus ntshai thiab tsis yog, qhov twg lawv siv thiab lawv tau txais li cas. Tab sis cia peb pib nrog luv luv digression rau hauv keeb kwm.
History
Keeb kwm ntawm hydrides pib nrog kev tshawb pom ntawm hydrogen. Lub ntsiab lus no tau pom los ntawm Henry Cavendish hauv xyoo pua 18th. Hydrogen, raws li koj paub, yog ib feem ntawm cov dej thiab yog lub hauv paus ntawm tag nrho lwm cov ntsiab lus ntawm lub sij hawm. Ua tsaug rau nws, lub hav zoov ntawm cov organic tebchaw thiab lub neej nyob rau hauv peb ntiaj chaw yog ua tau.
Ntxiv rau, hydrogen yog lub hauv paus rau ntau cov tshuaj inorganic. Ntawm lawv yog cov acids thiab alkalis, nrog rau cov cim binary compounds ntawm hydrogen nrog rau lwm cov ntsiab lus - hydrides. Hnub ntawm lawv thawj synthesis tsis paub meej, tab sis tsis yog hlau hydrides tau paub rau txiv neej txij thaum ancient sij hawm. Feem ntau ntawm cov no yog dej. Yog, dej yog oxygen hydride.
Tsis tas li cov chav kawm no suav nrog ammonia (cov ntsiab lus tseem ceeb ntawm ammonia), hydrogen sulfide, hydrogen chloride thiab cov khoom sib xws. Kawm paub ntxiv txog cov khoom ntawm cov tshuaj los ntawmchav kawm sib txawv thiab zoo kawg nkaus ntawm cov tebchaw no yuav tau tham hauv ntu tom ntej.
Lub cev muaj zog
Hydrides feem ntau yog roj. Txawm li cas los xij, yog tias peb siv cov hlau hydrides (lawv tsis ruaj khov nyob rau hauv cov xwm txheej ib txwm muaj thiab hnov mob sai heev nrog dej), ces cov no tuaj yeem yog cov khoom siv. Qee tus ntawm lawv (piv txwv li, hydrogen bromide) kuj muaj nyob hauv lub xeev ua kua.
Nws yooj yim tsis yooj yim sua kom muab cov lus piav qhia dav dav ntawm cov chav kawm loj ntawm cov tshuaj, vim tias lawv txhua tus sib txawv thiab, nyob ntawm lub caij uas ua rau cov hydride, ntxiv rau hydrogen, lawv muaj lub cev sib txawv thiab tshuaj muaj zog. Tab sis lawv tuaj yeem muab faib ua cov chav kawm, cov khoom sib txuas uas zoo sib xws. Hauv qab no peb yuav txiav txim siab txhua chav sib cais.
Ionic hydrides yog cov sib xyaw ntawm hydrogen nrog alkali lossis alkaline ntiaj teb hlau. Lawv yog cov tshuaj dawb, ruaj khov nyob rau hauv ib txwm muaj mob. Thaum rhuab, cov tebchaw no decompose rau hauv lawv cov hlau thiab hydrogen yam tsis muaj melting. Ib qho tshwj xeeb yog LiH, uas melts yam tsis muaj decomposition thiab, thaum tshav kub heev, hloov mus rau Li thiab H2.
Metal hydrides yog cov sib txuas ntawm cov hlau hloov pauv. Feem ntau lawv muaj qhov sib txawv ntawm qhov sib txawv. Lawv tuaj yeem sawv cev ua cov kua dej ntawm hydrogen hauv cov hlau. Lawv kuj muaj cov qauv siv lead ua hlau.
Rau covalent hydrides tsuas yog hom uas muaj ntau tshaj plaws hauv ntiaj teb: cov tebchaw ntawm hydrogen nrog cov hlau tsis yog hlau. Qhov dav ntawm kev faib tawm ntawm cov tshuaj no yog vim lawvkev ruaj ntseg siab, vim covalent daim ntawv cog lus yog qhov muaj zog tshaj plaws ntawm cov khoom siv tshuaj lom neeg.
Ua piv txwv, cov qauv rau silicon hydride yog SiH 4. Yog tias peb saib nws hauv ntim, peb yuav pom tias hydrogen tau nruj heev rau lub hauv paus silicon atom, thiab nws cov electrons hloov mus rau nws. Silicon muaj ib tug txaus siab electronegativity, yog li ntawd, nws muaj peev xwm mus nyiam electrons rau nws cov nucleus ntau zog, yog li txo qhov ntev ntawm daim ntawv cog lus ntawm nws thiab nyob sib ze atom. Thiab raws li koj paub, daim ntawv cog lus luv dua, nws muaj zog dua.
Nyob rau ntu tom ntej, peb yuav tham txog yuav ua li cas hydrides txawv ntawm lwm cov tebchaw nyob rau hauv cov nqe lus ntawm reactivity.
tshuaj muaj zog
Nyob rau ntu no nws tseem tsim nyog faib cov hydrides rau hauv tib pab pawg ib yam li yav dhau los. Thiab peb yuav pib nrog cov khoom ntawm ionic hydrides. Lawv qhov sib txawv tseem ceeb ntawm ob hom yog tias lawv nquag cuam tshuam nrog dej nrog tsim cov alkali thiab tso tawm ntawm hydrogen hauv daim ntawv roj. Cov tshuaj tiv thaiv ntawm hydride - dej yog tawg heev, yog li cov tebchaw feem ntau khaws cia yam tsis muaj dej noo. Qhov no ua tiav vim dej, txawm nyob hauv huab cua, tuaj yeem pib qhov kev hloov pauv txaus ntshai.
Cia peb qhia qhov sib npaug ntawm cov tshuaj tiv thaiv saum toj no siv cov piv txwv ntawm cov khoom xws li potassium hydride:
KH + H2O=KOH + H2
Raws li peb tuaj yeem pom, txhua yam yooj yim heev. Yog li ntawd, peb yuav txiav txim siab ntau qhov kev tshwm sim nthuav tawm yam ntxwv ntawm ob hom tshuaj uas peb piav qhia.
Hauv paus ntsiab lus, qhov seem ntawm kev hloov pauv uas peb tsis tau txheeb xyuas yog cov yam ntxwv ntawm txhua hom tshuaj. Lawv yogzoo li yuav hnov mob nrog hlau oxides los ua hlau, xws li dej los yog nrog hydroxide (tom kawg yog ib txwm rau alkali thiab alkaline ntiaj teb hlau).
Lwm qhov kev xav tau nthuav tawm yog thermal decomposition. Nws tshwm sim ntawm qhov kub thiab txias thiab dhau mus ua ntej tsim cov hlau thiab hydrogen. Peb yuav tsis nyob ntawm qhov kev tawm tsam no, txij li peb tau txheeb xyuas nws hauv ntu dhau los.
Yog li, peb tau txiav txim siab cov khoom ntawm hom binary compounds. Tam sim no nws yog lub sij hawm los tham txog kom tau lawv.
Kev tsim cov hydrides
Yuav luag tag nrho covalent hydrides yog natural compounds. Lawv yog cov ruaj khov heev, yog li lawv tsis tawg nyob rau hauv lub zog ntawm sab nraud. Nrog ionic thiab hlau hydrides, txhua yam yog qhov nyuaj me ntsis. Lawv tsis muaj nyob hauv cov xwm txheej, yog li lawv yuav tsum tau ua ke. Qhov no yog ua tau yooj yim heev: los ntawm cov tshuaj tiv thaiv ntawm kev sib cuam tshuam ntawm hydrogen thiab lub caij uas nws hydride yuav tsum tau.
Daim ntawv thov
Qee hydrides tsis muaj daim ntawv thov tshwj xeeb, tab sis feem ntau yog cov khoom tseem ceeb rau kev lag luam. Peb yuav tsis mus rau hauv cov ntsiab lus, vim hais tias txhua leej txhua tus tau hnov tias, piv txwv li, ammonia yog siv nyob rau hauv ntau qhov chaw thiab ua hauj lwm raws li ib tug indispensable tshuaj rau zus tau tej cov amino acids thiab organic compounds. Kev siv ntau hydrides yog txwv los ntawm lawv cov khoom siv tshuaj. Yog li ntawd, lawv tau siv tshwj xeeb hauv kev sim kuaj.
Daim ntawv thov yog ib ntu dav dhau rau cov chav kawm ntawm cov khoom no, yog li peb tau txwv peb tus kheej rau qhov tseeb dav dav. Hauv ntu tom ntej, peb yuav qhia koj li casntau ntawm peb, tsis muaj kev paub zoo, cuam tshuam tsis zoo (lossis tsawg kawg paub) tshuaj nrog ib leeg.
Qee qhov kev xav
Piv txwv li, qee cov neeg xav tias hydrogen hydride yog ib yam uas txaus ntshai. Yog tias koj tuaj yeem hu cov khoom no, ces tsis muaj leej twg ua nws. Yog tias koj xav txog nws, ces hydrogen hydride yog kev sib xyaw ntawm hydrogen nrog hydrogen, uas txhais tau hais tias nws yog H2 molecule. Tau kawg, cov pa roj no txaus ntshai, tab sis tsuas yog thaum sib xyaw nrog oxygen. Hauv nws daim ntawv dawb huv, nws tsis muaj kev phom sij.
Muaj ntau lub npe tsis meej. Lawv ntshai tus neeg tsis paub qab hau. Txawm li cas los xij, raws li kev xyaum qhia, feem ntau ntawm lawv tsis txaus ntshai thiab siv rau hauv tsev.
Zoo kawg
Lub ntiaj teb no ntawm chemistry loj heev, thiab peb xav tias yog tias tsis yog tom qab no, tom qab ob peb kab lus, koj yuav pom koj tus kheej. Tias yog vim li cas nws ua rau kev nkag siab rau koj tus kheej hauv nws txoj kev kawm nrog koj lub taub hau. Tib neeg tau tshawb pom ntau yam tshiab, thiab tseem tsis tau paub dua. Thiab yog tias nws zoo li koj tias tsis muaj dab tsi nthuav hauv thaj tsam ntawm hydrides, koj tau ua yuam kev loj heev.
