Qhov sib txawv tseem ceeb ntawm adhesion thiab cohesion yog qhov adhesion yog qhov attraction ntawm cov tshuaj los yog cov molecules uas tsis zoo sib xws whereas cohesion yog attraction ntawm cov molecules los yog cov khoom uas zoo sib xws.
Muaj ntau yam tshwm sim los piav txog tej yam uas peb saib hauv peb lub neej niaj hnub. Txawm hais tias qee zaum peb tsis tsom mus rau cov ntsiab lus me me no, lawv yog cov uas pab ua kom muaj sia nyob hauv ntiaj teb. Adhesion thiab cohesion yog ob yam zoo li no. Txawm hais tias lawv suab zoo sib xws, lawv yog cov ntsiab lus sib txawv kiag li.
Adhesion yog dab tsi?
Adhesion yog lub zog txaus nyiam ntawm ob hom molecules, uas txawv ntawm ib leeg. Piv txwv li, qhov attraction ntawm cov dej molecules nrog cov phab ntsa ntawm xylem hlab ntsha yog adhesion. Vim yog lub zog no, dej tuaj yeem taug kev los ntawm xylem hauv cov nroj tsuag. Tsis tas li ntawd, cov no yog cov rog sib txawv.
Nws muaj tsib lub tswv yim los piav qhia txog kev ua kom adhesion raws li hauv qab no:
- Mechanical adhesion
- Tshuaj adhesion
- Dispersive adhesion
- Electrostatic adhesion
- Diffusive adhesion
Nyob rau hauv mechanical adhesion, cov khoom nplaum tuav lub ntsej muag los ntawm kev sau rau hauv lub qhov lossis qhov pores hauv nws. Nyob rau hauv tshuaj adhesion, chemical bonds tsim, thiab lawv tuaj yeem yog ionic lossis covalent daim ntawv cog lus. Yog tias daim ntawv cog lus yog ionic, ces cov khoom siv hluav taws xob tuaj yeem pub dawb lossis nyiam, lossis lwm yam kev sib koom electron tuaj yeem muaj nyob rau hauv covalent bonding.
Lwm yam tshaj li cov no, cov ntawv cog lus sib txuas xws li cov ntawv cog lus hydrogen tuaj yeem koom nrog tuav ob yam khoom ua ke. Yog tias ob qho khoom raug tuav ua ke vim yog Van der Waals rog, peb tuaj yeem piav qhia qhov txheej txheem no los ntawm kev sib cais adhesion.
Daim duab 01: Kev hloov pauv yog vim ob qho tib si Adhesion thiab Cohesion
Ntxiv mus, thaum muaj me ntsis (ntev los yog lub cev) them sib cais hauv ib lub molecule, peb hais tias cov molecule tau dhau los ua polarized. Cov nqi sib txawv yuav nyiam ib leeg; li no, muaj zog txaus nyiam ntawm cov molecules. Ib qho hluav taws xob hla hauv cov khoom siv hluav taws xob tuaj yeem ua rau hluav taws xob sib txawv. Qhov sib txawv ntawm qhov sib txawv tuaj yeem ua rau muaj zog electrostatic ntawm cov khoom. Peb hu nws electrostatic adhesion.
Thaum ob hom molecules yog soluble hauv ib leeg, lawv tuaj yeem txav mus rau lwm qhov chaw; Yog li, nws ua rau diffusive adhesion. Lub zog ntawm adhesion rog nyob ntawm lub tshuab; raws li nws tshwm sim. Piv txwv li, yog tias thaj chaw sib tiv tauj loj dua, lub zog ntawm Van der Waals yog siab dua. Yog li ntawd, lub zog ntawm dispersive adhesion rog yog siab dua.
Kev sib haum xeeb yog dab tsi?
Cohesion yog lub zog sib xyaw ua ke ntawm ob lub molecules zoo sib xws. Piv txwv li, cov dej molecules muaj qhov sib txawv ntawm qhov sib txawv ntawm lawv. Cov cuab yeej ntawm dej no tso cai rau cov dej molecules mus nrog kev sib xws. Peb tuaj yeem piav qhia cov duab ntawm cov dej nag lossis qhov muaj nyob ntawm cov tee dej es tsis yog ib qho molecules los ntawm kev sib koom ua ke.
Daim duab 02: Tsim cov dej poob vim kev sib koom ua ke
Ntxiv mus, hydrogen bonding peev xwm ntawm cov dej molecules yog lub ntsiab yog vim li cas tom qab cohesion rog ntawm dej molecules. Txhua cov dej molecule tuaj yeem tsim plaub hydrogen bonds nrog lwm cov dej molecules; Yog li ntawd, kev sau ntawm attraction rog yog ntau zog. Electrostatic rog thiab Van der Waals rog ntawm cov molecules zoo sib xws kuj ua rau adhesion. Txawm li cas los xij, adhesion vim Van der Waals rog yog me ntsis qaug zog.
Qhov txawv ntawm Adhesion thiab Cohesion yog dab tsi?
Adhesion yog lub zog txaus nyiam ntawm ob hom molecules, uas sib txawv ntawm ib leeg thiab kev sib koom ua ke yog lub zog intermolecular ntawm ob lub molecules zoo sib xws. Yog li ntawd, qhov sib txawv tseem ceeb ntawm adhesion thiab cohesion yog qhov adhesion yog qhov attraction ntawm cov tshuaj los yog molecules uas tsis zoo sib xws whereas cohesion yog qhov attraction ntawm cov molecules los yog cov khoom uas zoo sib xws.
Ntxiv mus, lwm qhov sib txawv tseem ceeb ntawm adhesion thiab cohesion yog qhov adhesion suav nrog electrostatic attractions thaum cohesion suav nrog Van Der Waal rog thiab hydrogen bonding. Piv txwv li, cohesion yog nruab nrab ntawm ob lub molecules dej thiab adhesion yog nruab nrab ntawm cov dej molecules thiab phab ntsa ntawm xylem hlab ntsha.
Summary – Adhesion vs Cohesion
Adhesion thiab cohesion yog ob hom intramolecular rog. Qhov sib txawv tseem ceeb ntawm adhesion thiab cohesion yog qhov adhesion yog qhov kev nyiam ntawm cov tshuaj molecules uas tsis zoo sib xws whereas cohesion yog qhov attraction ntawm cov molecules los yog cov khoom uas zoo sib xws.
