Ngā Tauira Pātai me te Kōrero mō ngā Matū Waro i Hangaia ki ngā Mekameka Waro
Ko ngā matū waro he akomanga matua o ngā matū kei roto te waro me ētahi atu huānga, ko te nuinga ko te hauwai, te hāora, te hauota, te whanariki, me ngā halogen. Ko tētahi āhuatanga o ngā matū waro ko te noho mai o ngā mekameka waro, ka taea te hanga i ngā hanganga rerekē pērā i ngā mekameka tika, ngā mekameka peka, ngā mowhiti rānei. I roto i tēnei tuhinga, ka matapakihia e mātou ētahi tauira raruraru e pā ana ki ngā matū waro i hangaia mai i ngā mekameka waro, me ngā whakamārama.
Tauira Pātai 1
Pātai:
Ko te benzene tētahi o ngā matū kakara rongonui, ā, e ono ngā ngota waro e hanga ana i tētahi mowhiti. Whakamāramahia te hanganga Lewis o te benzene, me te whakamārama i te pumau o tēnei hanganga.
Kōrero:
Ko te tātai ngota o te Benzene ko C6H6. Ko tōna hanganga Lewis e whakaatuhia ana hei ono ngā ngota waro e hanga ana i te hexagon, me ia ngota waro e herea ana ki te ngota hauwai kotahi. He hononga takirua tauutuutu me ngā hononga takitahi kei ia ngota waro.
Koinei te whakaahuatanga o te hanganga Lewis o te benzene:
""
HH
\ /
C = C
/ \
CC
| |
CC
\ /
CC
| |
HH
""
Ko te ariā o te harurutanga e whakamārama ana i te pumau o te hanganga o te benzene, arā, ko te tūnga o ngā hononga takirua me te hononga takitahi ka taupatupatu i roto i tētahi hanganga he ranunga o ētahi hanganga harurutanga. Mā tēnei harurutanga ka wehea ngā irahiko π puta noa i te mowhiti, ā, ka nui ake te pumau o te ngota benzene.
Tauira Pātai 2
Pātai:
Whakatauhia te ingoa IUPAC o te matū e whai ake nei: CH3-CH2-CH(CH3)-CH2-CH3.
Kōrero:
He mekameka waro tika te matū, kotahi te peka. Ko te taahiraa tuatahi ko te whakatau i te mekameka waro roa rawa atu kei roto e rima ngā ngota waro, ka tapaina ko te pentane hei pūtake.
Muri iho, ko te peka i roto i te āhua o te rōpū methyl (-CH3) kei runga i te tuatoru o ngā waro mai i ngā pito e rua, nō reira ka hoatu e mātou te tau tūranga 3 mō tēnei peka.
Nō reira, ko te ingoa IUPAC o te pūhui ko 3-methylpentane.
Tauira Pātai 3
Pātai:
Tatauhia te maha o ngā isomers hanganga mō te alkane me te tātai ngota C5H12.
Kōrero:
He maha ngā isomers hanganga o ngā alkana me ngā ngota waro e rima (pentane):
1. Pentane (n-pentane):
""
CH3-CH2-CH2-CH2-CH3
""
2. 2-metilpētana (isopentane):
""
CH3
|
CH3-CH-CH2-CH3
""
3. 2,2-dimethylpropane (neopentane):
""
CH3
|
CH3-C-CH3
|
CH3
""
I te mea kua kore he hanganga rerekē me te maha o ngā ngota waro rite tonu, me te kore e whakarerekē i te raupapatanga o te mekameka waro, te tūranga rānei o te rōpū metil, e toru noa iho ā tātou isomers hanganga mō te C5H12.
Tauira Pātai 4
Pātai:
Tuhia te hanganga o te matū etanoru (C2H5OH) me te whakaahua i ōna āhuatanga ā-tinana, ā-matū hoki.
Kōrero:
Ko te hanganga o te matū etanoru penei:
""
HH
\ |
HCC-OH
| |
HH
""
Ngā āhuatanga ā-tinana o te etanoru:
1. He wai mārama, kore tae te etanoru, he kakara motuhake tōna.
2. Ko tōna ira kohua he 78.37°C, ā, ko tōna ira tio he -114.1°C.
3. He pai te wairewa i roto i te wai nā te mea ka taea e ia te hanga hononga hauwai me ngā ngota wai.
Ngā āhuatanga matū o te etanoru:
1. Ka taea e te etanoru te tauhohe ki ngā waikawa carboxylic hei hanga i ngā ester.
2. Ka taea hoki e te etanoru te whakapūngao hei acetaldehyde, kātahi hei waikawa acetic.
3. Ka mura te etanoru i te hau, ā, he iti noa te kitea o te mura kikorangi.
Tauira Pātai 5
Pātai:
Whakatauhia te whirihoranga R/S mō te waro chiral i roto i te ngota waikawa lactic, ko tōna tātai ngota CH3-CH(OH)-COOH.
Kōrero:
Ngā taahiraa hei whakarite i te whirihoranga R/S:
1. Tāutuhia ngā ngota waro chiral (stereoisomers) i roto i te ngota. Ko ngā waro chiral i roto i te waikawa lactic ko ngā ngota waro e honoa ana ki ngā rōpū -OH, -COOH, -CH3, me te -H.
2. Tautapahia ngā kaupapa matua i runga i te tau ngota (ngā ture Cahn-Ingold-Prelog): -OH (kaupapa matua 1), -COOH (kaupapa matua 2), -CH3 (kaupapa matua 3), me -H (kaupapa matua 4).
3. Tōhua te rōpū kei raro te kaupapa matua (-H) ki muri.
4. Tirohia te raupapatanga mai i te 1 ki te 3. Ki te mea kei te taha maui, ko te whirihoranga ko S; ki te mea kei te taha matau, ko R te whirihoranga.
Nā reira, mō te waikawa lactic,
– Te Matua: -OH (1), -COOH (2), -CH3 (3)
– Ko te raupapa mai i te 1 ki te 3 he mea huri ki te matau, nō reira ko te whirihoranga he R.
Nō reira, he whirihoranga R tō te waikawa miraka i tōna waro kiral.
Whakamutunga
He mea nui te mārama ki te hanganga me te whakaingoa o ngā pūhui waro, inā koa ko ērā e titoa ana i ngā mekameka waro, i roto i te matū waro. Kei roto i tēnei tuhinga ētahi tauira raruraru me ngā kōrero, e kapi ana i ngā hanganga orooro, te whakaingoa IUPAC, te isomerization, me ngā whirihoranga stereoisomer. Ko te tumanako ka āwhina tēnei kōrero i ngā kaipānui ki te mārama ake me te whakamahi i ngā ariā nui i roto i te matū waro.
