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Te tikanga whakatau o te hydroxypropyl methylcellulose

Ingoa tikanga: hypromellose — te whakatau o te hydroxypropoxy — te whakatau o te hydroxypropoxy

Te whānuitanga o te tono: Ka whakamahia e tenei tikanga te tikanga whakatau hydroxypropoxy hei whakatau i te ihirangi o te hydroxypropoxy i roto i te hypromellose.

Ko tenei tikanga e pa ana ki te hypromellose.

Tikanga o te tikanga: Tatauhia te ihirangi o te hydroxypropoxy i roto i te hua whakamatautau i runga i te tikanga whakatau hydroxypropoxy.

Reagent:

1. 30% (g/g) chromium trioxide otinga

2. Te wairewa tairitenga konutai konutai (0.02mol/L)

3. Te otinga tohu Phenolphthalein

4. konutai bicarbonate

5. Waimeha waikawa pungatara

6. Te pāhare pāporo iodide

7. Wairewa titration konutai thiosulfate (0.02mol/L)

8. Te otinga tohu maaka

taputapu:

Whakaritenga tauira: 1. Te wairewa wairewa tiritiri konutai (0.02mol/L)

Te Whakaritenga: Tangohia te 5.6mL o te wairewa konutai waiwaro maamaa kukū, tāpirihia he wai matao hou kohuatia kia 1000mL.

Te whakatikatika: Me tango kia 6 karamu o te pāhare pāporo hauwai phthalate kua whakamarokehia ki te 105°C ki te taumaha tonu, paunatia tika, tāpirihia te 50mL o te wai makariri kātahi anō ka kohuatia, ruru kia memeha noa; tāpirihia kia 2 ngā pata o te wairewa tohu phenolphthalein, whakamahia tenei titration Wai, ka tata ki te pito mutunga, me tino rewa te konupora hydrogen phthalate, ka titrated kia mawhero te otinga. Ia 1mL o te konutai wairewa wairewa titration (1mol/L) he rite ki te 20.42mg o te konutai hauwai phthalate. Tātaihia te kukū o tēnei otinga i runga i te kai o tēnei otinga me te nui o te pāhare pāporo hauwai phthalate i tangohia. Me waimeha ine kia 5 nga wa kia 0.02mol/L te kukū.

Rokiroki: Whakanohoia ki roto i te pounamu kirihou polyethylene ka hiritia; E 2 nga kohao o te mono, ka kuhuhia kia 1 ngongo karaihe ki ia kohao, 1 ngongo ka honoa ki te ngongo houra kotakota, ka whakamahia kia 1 ngongo mo te ngote i te wai.

2. Te otinga tohu Phenolphthalein

Tangohia kia 1 karamu o te phenolphthalein, tāpirihia te 100mL o te waihā kia memeha

3. Wairewa titration konutai thiosulfate (0.02mol/L)

Te Takanga: Me mau ki te 26 karamu o te konutai thiosulfate me te 0.20 karae o te konutai warowaikawa, tāpirihia he wai matao kātahi anō ka kohuatia kia rewa ki te 1000mL, ruru pai, ka tātari i muri i te tu mo te 1 marama.

Whakariterite: tangohia kia 0.15 karamu o te pāhare pāporo dichromate kua whakamarokehia ki te 120°C me te taumaha tonu, kia tika te pauna, hoatu ki roto i te pounamu iodine, tāpirihia te 50mL wai kia memeha, tāpirihia te 2.0g pāhare pāporo iodide, ruru ata kia memeha, tāpirihia 40mL o te waikawa pungatara waimeha, ruru pai ka hiritia; i muri i te 10 meneti i roto i te waahi pouri, taapirihia he 250mL wai kia waimeha, a ka taia te wairewa ki te tata ki te pito mutunga, taapirihia te 3mL o te wairewa tohu maaka, haere tonu te titrate tae noa ki te ngaro o te tae kahurangi ka kakariki kanapa, ka puta te hua. ka whakamahia hei whakatikatika Whakamaatau. Ko ia 1mL o te konutai thiosulfate (0.1mol/L) he rite ki te 4.903g o te konutai dichromate. Tātaihia te kukū o te otinga i runga i te kai o te otinga me te nui o te pāhare pāporo dichromate i tangohia. Me waimeha ine kia 5 nga wa kia 0.02mol/L te kukū.

Mena kei runga ake te pāmahana rūma i te 25°C, me whakamatao te pāmahana o te otinga tauhohenga me te wai waimeha ki te 20°C.

4. Wairewa tohu māngaro

Tangohia 0.5g o te māngaro wairewa, tāpiri 5mL o te wai, me te oho pai, ka āta ringihia ki te 100mL o te wai kohua, oho rite tāpiri koe, haere tonu ki te kohua mo te 2 meneti, kia whakamatao, ringihia i roto i te supernatant, ka whiwhi koe. Me whakarite hou tenei otinga i mua i te whakamahi.

Nga mahi: Tangohia te 0.1g o tenei hua, ka ata paunatia, ka maka ki roto i te pounamu D, ka tapirihia he 10mL o te 30% (g/g) otinga cadmium trichloride. Whakakiia te ngongo whakangao mamaoa B ki te wai ki te hononga, ka honoa te wae whakangao. Rukuhia te B me te D ki roto i te pati hinu (ka taea te glycerin), kia rite te taumata wai o te pati hinu ki te taumata wai o te otinga cadmium trichloride i roto i te pounamu D, whakakāhia te wai whakamatao, a ki te tika, waiho ka rere te awa hauota ki roto, ka whakahaere i tana tere rere ki te 1 mirumiru ia hekona. I roto i te 30 meneti, whakanekehia te pāmahana o te pati hinu ki te 155ºC, ka pupuri i tenei pāmahana kia kohia te 50 mL o te distillate, tangohia te ngongo condenser mai i te wahanga hautau, horoia ki te wai, horoi ka hanumi ki roto i te wai kua kohia, tāpirihia te 3 pata o te wairewa tohu phenolphthalein, ka whakamahi i te Titrate kia 6.9-7.1 te uara pH (i ine ki te mita kawakawatanga), tuhia te rōrahi V1 (mL) kua pau, katahi ka tapirihia te 0.5g konutai bicarbonate me te 10mL o te waikawa pungatara waimeha, waiho. Me noho kia kore ra ano te hua o te waro hauhā, tāpirihia he 1.0 karamu o te pāhare pāporo iodide, hiritia kia pai, ruru pai, hoatu ki te wahi pouri mo te 5 meneti, tāpirihia te 1mL o te wairewa tohu māngaro, tiritihia ki te pito mutunga ki te konutai thiosulfate titration otinga (0.02mol/L), ka tuhi i te rōrahi V2 (mL) kua pau. I roto i tetahi atu whakamatautau tuwhera, tuhia nga pukapuka Va me Vb (mL) o te wairewa titration konutai hydroxide (0.02mol/L) me te otinga titration konutai thiosulfate (0.02mol/L) ia. Tātaihia te ihirangi hydroxypropoxyl.


Te wa tuku: Apr-14-2023
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