VSEPR Molecular Shape Theory: Kunzwisisa Kwakadzama
Pengantar
Dzidziso yeValence Shell Electron Pair Repulsion (VSEPR) yechimiro chemamorekuru idzidziso huru mukemistri inoshandiswa kufanotaura chimiro kana geometry yemamorekuru anobva muzvisungo zviri pakati pemaatomu. Dzidziso iyi chishandiso chakakosha kune vanoongorora makemikari mukunzwisisa chimiro chemamorekuru uye hunhu hwakasiyana-siyana hwemakemikari nehwepanyama hwavanogadzira. Chinyorwa chino chichapa pfupiso yakadzama yedzidziso yeVSEPR, misimboti yayo yekutanga, uye maumbirwo akasiyana-siyana emamorekuru anogona kufanotaurwa uchishandisa dzidziso iyi.
Nheyo dzekutanga dzedzidziso yeVSEPR
Dzidziso yeVSEPR yakavakirwa papfungwa yekuti maerekitironi anotenderedza atomu anodzingana, zvichivaita kuti vatore nzvimbo dzinoderedza kudzongonyedzwa uku. Maerekitironi aya anogona kuva mapeya ekubatanidza kana kuti mapeya ega ega.
Nheyo huru dzedzidziso yeVSEPR ndeidzi:
1. Kudzongonyedza pakati pemaerekitironi maviri: Maerekitironi maviri akakomberedza atomu yepakati anoedza kuramba ari kure zvakanyanya sezvinobvira kuderedza kudzongonyedza.
2. Mhando dzemaerekitironi maviri: Maerekitironi maviri anowanzo tora nzvimbo yakawanda kupfuura maerekitironi maviri akabatana nekuti maerekitironi maviri ari pedyo nenucleus uye haana kusungirirwa kune mamwe maatomu.
AX Notation muVSEPR Theory
Kutsanangura chimiro chemorekuru uchishandisa dzidziso yeVSEPR, AXE notation inoshandiswa, apo:
– A inomiririra atomu iri pakati pemorekuru.
– X inomiririra huwandu hwema "bonding pairs" emaerekitironi akabatana neatomu yepakati.
– E inomiririra huwandu hwemaerekitironi maviri ari pakati peatomu.
Chimiro cheMolecular Maererano neVSEPR Theory
Zvinotevera mamorekuru akawanda ejometri anogona kutsanangurwa uchishandisa dzidziso yeVSEPR yakavakirwa paAXE notation:
1. Mutsetse (AX2):
– Mienzaniso: BeCl2, CO2.
– Mumorekuru yakatsetseka, mune mapeya maviri emaerekitironi anobatana ari kure nemadhigirii zana nemakumi masere. Hapana maerekitironi ari maviri paatomu yepakati.
2. Trigonal Planar (AX3):
- Muenzaniso: BF3.
– Muchimiro ichi, maerekitironi matatu anobatana anopararira mundege imwe chete pamakona e120-degree. Hapana maerekitironi maviri ega ega ari paatomu yepakati.
3. Yakakombama kana kuti yakaita seV (AX2E kana AX2E2):
– Muenzaniso: SO2 (AX2E), H2O (AX2E2).
– Muchimiro ichi, kune maerekitironi maviri ane ma bonding uye rimwe kana maviri ane ma lone pairs. Ma lone pairs anosunda ma bonding pairs pamwe chete, zvichikonzera chimiro chakakombama.
4. Tetrahedral (AX4):
– Muenzaniso: CH4.
– Kune maerekitironi mana ane ma bonding akarongwa zvakaenzana pakona ye109.5 degrees. Hapana maerekitironi maviri ega ega paatomu yepakati.
5. Piramidhi ine Trigonal (AX3E):
- Muenzaniso: NH3.
– Kune maerekitironi matatu ane ma bonding uye rimwe chete. Mapeya ari ega anosundira ma bonding maviri pakati, zvichiita piramidhi ine trigonal ine rimwe chete pamusoro.
6. Trigonal Bipyramidal (AX5):
– Muenzaniso: PCl5.
– Kune maerekitironi mashanu ane ma bonding ane maerekitironi matatu ari mu plane imwe (120 degrees angle) uye mamwe maerekitironi maviri ari munzvimbo dze axial (90 degrees angle).
7. Seesaw (AX4E):
- Muenzaniso: SF4.
– Kune maerekitironi mana ane ma bonding uye rimwe chete. Maitiro e seesaw anoumbwa nekuti maerekitironi maviri aya anoronga kuti aderedze kudzongonyedzwa.
8. Yakaumbwa neT (AX3E2):
– Muenzaniso: ClF3.
- Kune ma "bonding pairs" matatu ema "electrons" uye maviri ari ega, zvichigadzira chimiro che "T-shaped geometry".
9. Octahedral (AX6):
- Muenzaniso: SF6.
– Kune maerekitironi matanhatu ane ma bonding akapararira pamwe chete nemaaxes matatu eCartesian pamakona e90-degree. Hapana maerekitironi maviri ari ega paatomu repakati.
10. Piramidhi Yesikweya (AX5E):
– Muenzaniso: BrF5.
- Kune ma "bonding electron pairs" mashanu uye "one electron pairs" imwe chete, zvichigadzira piramidhi ine sikweya ine sikweya.
11. Purani Yesikweya (AX4E2):
- Muenzaniso: XeF4.
– Kune maerekitironi mana ane ma bonding uye maviri ane ma lone pairs, zvichikonzera planar geometry ne one pairs dziri pakatarisana ne bonding pairs.
Zvipingamupinyi uye Mashandisirwo edzidziso yeVSEPR
Kunyangwe dzidziso yeVSEPR ichibatsira zvikuru, ine zvimwe zvipingamupinyi. Mamwe mamorekuru akaomarara haaenderane nefungidziro yeVSEPR, kunyanya kana atomu yepakati yakakura kwazvo kana kana mabhondi ari akawanda-covalent. Semuenzaniso, dzidziso yeVSEPR haisi nguva dzose yakarurama pakufanotaura chimiro chemamorekuru ane transition metals ane d-orbitals anobatanidzwa mukubatana.
Pasinei neizvi, VSEPR ichiri kunzi chishandiso chinobatsira zvikuru mudzidzo yekemesitiri uye kuongorora marongerwo emamorekuru. Dzidziso iyi yakashandiswa zvakanyanya muzvikamu zvakasiyana-siyana zvekemesitiri, kusanganisira kemesitiri yeorganic, kemesitiri isina organic, uye biochemistry.
Mhedziso
Dzidziso yeVSEPR yechimiro chemamorekuru inopa nzira yakakosha uye inoshanda yekufanotaura chimiro chemamorekuru zvichibva pahuwandu hwemaerekitironi maviri akakomberedza atomu repakati. Uchishandisa misimboti yekutanga yekudzora maerekitironi maviri uye AXE notation, mamorekuru akasiyana-siyana anogona kufanotaurwa nemazvo muzviitiko zvakawanda. Kunyangwe dzidziso iyi iine zvimwe zvisingakwanisike, kubatsira kwayo mudzidzo nekushandiswa kwesainzi hakurambiki. Kunzwisisa VSEPR kunotibatsira kunzwisisa zviri nani chimiro chemamorekuru uye hunhu, pakupedzisira zvichibatsira kutsvaga nekuvandudza makemikari.
