Mienzaniso yeMibvunzo Inotaura NezveCovalent Bonds
Pendauluan
Chisungo checovalent rudzi rwechisungo chemakemikari umo maatomu maviri anogovana maerekitironi maviri kana kupfuura kuti awane chimiro chakasimba chemaerekitironi, senge mumagasi akanaka. Chisungo ichi chinowanzoitika pakati pemaatomu asiri esimbi ane maerekitironi akakwira uye asina kusiyana zvakanyanya. Kuumbwa kwechisungo checovalent kunoita basa rakakosha mumakemikari eorganic neeinorganic uye ndiyo hwaro hwemakemikari akawanda atinosangana nawo zuva nezuva. Muchinyorwa chino, tichakurukura mienzaniso yakati wandei inosanganisira zvisungo zvecovalent uye kupa mhinduro kutibatsira kunzwisisa zviri nani.
Mibvunzo yemuenzaniso nekukurukurirana
Mubvunzo 1
Sarudza rudzi uye huwandu hwezvisungo zve covalent zvakagadzirwa muH2O (mvura) molecule.
Kukurukurirana:
Molekyuru yemvura ine atomu imwe chete yeokisijeni (O) uye maatomu maviri ehydrogen (H).
1. Kugadzika kweElectron:
– Okisijeni: 1s² 2s² 2p⁴ (maerekitironi ese masere)
– Hydrogen: 1s¹ (erekitironi imwe chete)
Okisijeni inoda mamwe maerekitironi maviri kuti iite octet configuration (maerekitironi masere mugoko rayo rekunze), nepo atomu yega yega yehydrogen ichida erekitironi imwe chete kuti iite duplet configuration (maerekitironi maviri mugoko reK).
2. Kuumbwa kweCovalent Bonds:
– Atomu yega yega yeHydrogen inogovana erekitironi imwe neatomu yeOxygen.
– Okisijeni inogovana maerekitironi maviri nemaatomu maviri eHydrogen, rimwe chete paatomu imwe neimwe.
Saka, mabhondi maviri e covalent anoumbwa mumorekuru yeH2O, rimwe riri pakati peatomu yeOxygen neatomu yeHydrogen zvakateerana.
Mubvunzo 2
Nyora chimiro chaLewis chemorekuru yemethane (CH₄).
Kukurukurirana:
Methane ine atomu imwe chete yekabhoni (C) uye maatomu mana ehydrogen (H).
1. Kugadzika kweElectron:
– Kabhoni: 1s² 2s² 2p² (maerekitironi matanhatu ese)
– Hydrogen: 1s¹ (erekitironi imwe chete)
Kabhoni ine maerekitironi mana evalence (2s² 2p²), uye inoda mamwe maerekitironi mana kuti isvike pa octet.
2. Kuumbwa kweCovalent Bonds:
– Atomu yega yega yeHydrogen inogovana erekitironi imwe neatomu yeCarbon.
– Kabhoni ine maerekitironi mana nemaatomu mana eHydrogen, rimwe chete paatomu imwe neimwe.
Maumbirwo emethane eLewis ndeaya anotevera:
``
H
|
H – C – H
|
H
``
Kabhoni iri pakati nepakati ine ma "single covalent bonds" mana kune maatomu mana ehydrogen.
Mubvunzo 3
Sarudza chimiro cheLewis uye chimiro chemorekuru checarbon dioxide (CO₂).
Kukurukurirana:
Kabhoni dhayiokisijeni ine atomu imwe chete yekabhoni (C) uye maatomu maviri eokisijeni (O).
1. Kugadzika kweElectron:
– Kabhoni: 1s² 2s² 2p² (maerekitironi matanhatu ese)
– Okisijeni: 1s² 2s² 2p⁴ (maerekitironi ese masere)
Kabhoni ine maerekitironi mana evalence, nepo atomu yega yega yeokisijeni iine matanhatu. Kabhoni inoda mamwe maerekitironi mana kuti ive octet, nepo atomu yega yega yeokisijeni ichida mamwe maviri.
2. Kuumbwa kweCovalent Bonds:
– Kabhoni inogovana maerekitironi maviri neatomu yega yega yeOxygen.
– Zvisungo zviviri zve covalent zvinoumbwa pakati peCarbon neOxygen yega yega.
Chimiro cheLewis cheCO₂ ndechekuti:
``
O = C = O
``
Chimiro chemolekyuri chakarongeka nekona yechisungo che180°.
Mubvunzo 4
Verenga huwandu hwese hwemaerekitironi evalence uye dhirowa chimiro cheLewis chemorekuru yeammonia (NH₃).
Kukurukurirana:
Amoniya ine atomu imwe chete yenitrogen (N) uye maatomu matatu ehydrogen (H).
1. Kugadzika kweElectron:
– Nitrogen: 1s² 2s² 2p³ (maerekitironi manomwe ese)
– Hydrogen: 1s¹ (erekitironi imwe chete)
Nitrogen ine maerekitironi mashanu evalence, ichida mamwe maerekitironi matatu kuti ive octet.
2. Huwandu Hwese hweMaerekitironi eValence:
– Nitrogen: maerekitironi mashanu evalensi.
– Hydrogen (maatomu matatu): maerekitironi matatu (erekitironi rimwe paatomu imwe neimwe).
Maerekitironi ese evalensi = 5 + 3 = 8 maerekitironi evalensi.
3. Kuumbwa kweCovalent Bonds:
– Nitrogen inogovana erekitironi imwe chete neatomu yega yega yeHydrogen.
Maumbirwo eLewis eNH₃ ndeekuti:
``
H
|
H – N – H
|
``
Uye maerekitironi maviri akasununguka (one pair) ari munitrogen.
Mubvunzo 5
Dhirowa uye tsanangura chimiro cheLewis che nitrate ion (NO₃⁻).
Kukurukurirana:
Iyo nitrate ion isanganiswa yepolyatomic ine nitrogen imwe (N) uye maoxygen matatu (O), uye ine negative charge.
1. Kugadzika kweElectron:
– Nitrogen: 1s² 2s² 2p³ (maerekitironi manomwe ese)
– Okisijeni: 1s² 2s² 2p⁴ (maerekitironi ese masere)
Nitrogen ine maerekitironi mashanu evalence, nepo okisijeni imwe neimwe iine maerekitironi matanhatu evalence.
2. Huwandu Hwese hweMaerekitironi eValence:
– Nitrogen: maerekitironi mashanu.
– Okisijeni (maatomu matatu): maerekitironi gumi nemasere (maerekitironi matanhatu paatomu imwe neimwe).
– Zvimwe zvinokonzerwa nemaion asina kunaka: 1 electron.
Maerekitironi ese eValensi = 5 + 18 + 1 = 24 maerekitironi eValensi.
3. Kuumbwa kweCovalent Bonds uye Kugadzirira Lewis Structures:
– Nitrogen inoumba chisungo chakapetwa kaviri nerimwe remaatomu eokisijeni uye chisungo chimwe chete nemamwe maatomu maviri eokisijeni.
- Kugoverwa kwakaenzana kwechaji isina kunaka pakati pemaatomu maviri eokisijeni ane mabhondi mamwechete kunosanganisira kurira kwesimba.
Maumbirwo aLewis eNO₃⁻ ndeekuti:
``
O
/
YAKABVA = O
``
Asi chiratidzo che resonance chinofanira kuwedzerwa kuti chitsanangure delocalization ye electron.
Mhedziso
Kubatana kweCovalent ipfungwa huru mukemistri, uko maatomu anogovana maerekitironi kuti awane kugadzikana. Kunzwisisa maitiro ekudhirowa maumbirwo eLewis, kuverenga maerekitironi eValence, uye kuona maumbirwo emamorekuru hunyanzvi hwakakosha hwekunzwisisa zvakadzama maitiro emakemikari. Kuburikidza nemienzaniso iri pamusoro, zvinotarisirwa kuti vaverengi vachanzwisisa zviri nani kuumbwa uye hunhu hwezvisungo zvecovalent.
