cov txheej txheem sim
Lub npe ntawm txoj kev: hypromellose - kev txiav txim siab ntawm pawg hydroxypropoxy - kev txiav txim siab ntawm pawg hydroxypropoxy
Scope ntawm daim ntawv thov: Txoj kev no siv txoj kev txiav txim siab hydroxypropoxy los txiav txim siab cov ntsiab lus ntawm hydroxypropoxy hauv hypromellose. Txoj kev no siv tau rau hypromellose.
Lub hauv paus ntsiab lus ntawm txoj kev:Xam qhovcov ntsiab lus ntawm hydroxypropoxy hauv cov khoom kuaj raws li txoj kev txiav txim siab hydroxypropoxy.
Tshuaj Reagent:
1. 30% (g/g) chromium trioxide kua
2. Hydroxide
3. Cov tshuaj qhia txog Phenolphthalein
4. Sodium bicarbonate
5. Txo cov kua qaub sulfuric
6. Potassium iodide
7. Kev daws teeb meem sodium thiosulfate titration (0.02mol/L)
8. Cov tshuaj qhia txog hmoov txhuv nplej siab
cov khoom siv:
Kev npaj qauv:
1. Kev daws teeb meem sodium hydroxide titration (0.02mol/L)
Kev Npaj: Siv 5.6mL ntawm cov kua sodium hydroxide ntshiab, ntxiv dej txias uas nyuam qhuav npau kom ua rau nws yog 1000mL.
Kev Kho Kom Zoo: Siv li 6g ntawm cov qauv potassium hydrogen phthalate qhuav ntawm 105 ° C kom qhov hnyav tas li, hnyav nws kom raug, ntxiv 50mL ntawm cov dej txias tshiab, co kom nws yaj ntau li ntau tau; ntxiv 2 tee ntawm phenolphthalein qhia cov kua, siv cov kua titration no, thaum mus txog qhov kawg, cov potassium hydrogen phthalate yuav tsum yaj tag nrho, thiab titrated kom txog thaum cov kua ua xim liab. Txhua 1mL ntawm sodium hydroxide titration kua (1mol / L) yog sib npaug rau 20.42mg ntawm potassium hydrogen phthalate. Xam qhov concentration ntawm cov kua no raws li kev noj cov kua no thiab qhov ntau ntawm potassium hydrogen phthalate noj. Quantitatively dilute 5 zaug kom ua rau qhov concentration 0.02mol / L.
Kev Khaws Cia: Muab tso rau hauv lub raj mis yas polyethylene thiab kaw kom ruaj; muaj 2 lub qhov hauv lub qhov ntsaws, thiab 1 lub raj iav raug ntxig rau hauv txhua lub qhov, 1 lub raj txuas nrog lub raj mis dej qab zib, thiab 1 lub raj siv rau kev nqus cov kua tawm.
2. Cov tshuaj qhia txog Phenolphthalein Siv 1g ntawm phenolphthalein, ntxiv 100mL ntawm ethanol kom yaj
3. Kev daws teeb meem sodium thiosulfate titration (0.02mol/L) Kev Npaj: Siv 26g ntawm sodium thiosulfate thiab 0.20g ntawm anhydrous sodium carbonate, ntxiv cov dej txias tshiab kom yaj rau hauv 1000mL, co zoo, thiab muab tso rau 1 lub hlis lim. Kev ntsuas: siv li 0.15g ntawm tus qauv potassium dichromate qhuav ntawm 120 ° C nrog qhov hnyav tas li, ntsuas nws kom raug, muab tso rau hauv lub raj mis iodine, ntxiv 50mL dej kom yaj, ntxiv 2.0g ntawm potassium iodide, co maj mam kom yaj, ntxiv 40mL ntawm dilute sulfuric acid, Co zoo thiab kaw kom nruj; tom qab 10 feeb hauv qhov chaw tsaus ntuj, ntxiv 250mL dej kom dilute, thiab thaum cov tshuaj raug titrated mus txog qhov kawg, ntxiv 3mL ntawm cov hmoov txhuv nplej siab qhia cov tshuaj, txuas ntxiv titration kom txog thaum xim xiav ploj mus thiab dhau los ua ntsuab ci, thiab cov txiaj ntsig titration siv ua kev kho dawb paug. Txhua 1mL ntawm sodium thiosulfate (0.1mol/L) yog sib npaug rau 4.903g ntawm potassium dichromate. Xam qhov concentration ntawm cov tshuaj raws li kev siv cov tshuaj thiab qhov ntau ntawm potassium dichromate uas tau noj. Ua kom muaj pes tsawg dilute 5 zaug kom ua rau qhov concentration 0.02mol/L. Yog tias qhov kub hauv chav tsev siab tshaj 25°C, qhov kub ntawm cov tshuaj tiv thaiv thiab dej dilution yuav tsum txias txog li 20°C.
4. Cov tshuaj qhia txog hmoov txhuv nplej siab Siv 0.5g ntawm cov hmoov txhuv nplej siab uas yaj tau, ntxiv 5mL dej thiab do kom zoo, tom qab ntawd maj mam ncuav rau hauv 100mL dej npau, do thaum ntxiv nws, txuas ntxiv npau rau 2 feeb, cia kom txias, nchuav cov supernatant tawm, thiab nws npaj txhij.
Cov tshuaj no yuav tsum tau npaj tshiab ua ntej siv.
Cov kauj ruam ua haujlwm: Siv 0.1g ntawm cov khoom no, hnyav nws kom raug, muab tso rau hauv lub raj mis distillation D, ntxiv 10mL ntawm 30% (g/g) cadmium trichloride kua. Sau lub raj mis tsim pa B nrog dej rau qhov sib koom ua ke, thiab txuas lub tshuab distillation. Muab ob qho tib si B thiab D rau hauv lub dab da dej roj (nws tuaj yeem yog glycerin), ua kom qib kua ntawm lub dab da dej roj sib xws nrog qib kua ntawm cadmium trichloride kua hauv lub raj mis D, tig rau dej txias, thiab yog tias tsim nyog, cia cov dej nitrogen ntws mus rau hauv thiab tswj nws qhov ntws mus rau 1 lub npuas ib ob. Hauv 30 feeb, nce qhov kub ntawm lub dab dej roj mus rau 155ºC, thiab tswj qhov kub no kom txog thaum 50 mL ntawm cov distillate tau sau, tshem lub raj condenser ntawm lub fractionation column, yaug nrog dej, ntxuav thiab sib xyaw rau hauv cov tshuaj sau, ntxiv 3 tee ntawm phenolphthalein indicator solution, thiab titrate rau Tus nqi pH yog 6.9-7.1 (ntsuas nrog lub ntsuas acidity), sau cov ntim noj V1 (mL), tom qab ntawd ntxiv 0.5g ntawm sodium bicarbonate thiab 10mL ntawm dilute sulfuric acid, cia nws sawv kom txog thaum tsis muaj carbon dioxide ntxiv lawm, ntxiv 1.0g ntawm potassium iodide, thiab kaw nws, Co zoo, muab tso rau hauv qhov tsaus ntuj rau 5 feeb, ntxiv 1mL ntawm starch indicator solution, titrate nrog sodium thiosulfate titration solution (0.02mol/L) mus rau qhov kawg, sau cov ntim noj V2 (mL). Hauv lwm qhov kev sim dawb paug, sau cov ntim Va thiab Vb (mL) ntawm cov tshuaj sodium hydroxide titration uas tau noj (0.02mol/L) thiab cov tshuaj sodium thiosulfate titration (0.02mol/L) raws li.
Lub sijhawm tshaj tawm: Plaub Hlis-25-2024