Ammonium Sulfate CAS 7783-20-2 Cov ntsiab lus 99.0 ~ 100.5%

(NH4)2SO4 132.14
Ammonium sulfate [7783-20-2].
DEFINITION
Ammonium Sulfate muaj NLT 99.0% thiab NMT 100.5% ntawm (NH4) 2SO4.
IDENTIFICATION
• A. Identification Tests-General, Ammonium <191>: Kev daws teeb meem (1 ntawm 20) ua tau raws li qhov yuav tsum tau ua.
• B. Identification Tests-General, Sulfate <191>: Kev daws teeb meem (1 ntawm 20) ua tau raws li qhov yuav tsum tau ua.
QHIA
• Cov txheej txheem
Qauv: 2.5 g ntawm ammonium sulfate
Titrimetric system
(Saib Titrimetry <541>.)
Hom: Residual titration
Titrant: 1 N sodium hydroxide VS
Tom ntej: 1 N sulfuric acid VS
Kev kuaj pom qhov kawg: Colorimetric
Tsis muaj: 50.0 mL ntawm 1 N sodium hydroxide VS, ntsuas kom raug
Kev Ntsuam Xyuas: Ntxiv Cov Qauv rau 500-mL conical flask thiab yaj hauv 50 mL dej.Ntxiv 50.0 mL ntawm 1 N sodium hydroxide VS, tso lub lim funnel loosely nyob rau hauv lub caj dab ntawm lub hwj, thiab boil kom txog thaum ammonia raug tshem tawm (kwv yees li 10-15 min), raws li tau txiav txim nrog litmus daim ntawv.Txias, ntxiv 0.15 mL ntawm thymol xiav TS, thiab titrate ntau tshaj sodium hydroxide nrog 1 N sulfuric acid VS.Ua ib qho kev txiav txim siab dawb paug.
Xam cov feem pua ​​​​ntawm ammonium sulfate [(NH4) 2SO4] hauv cov qauv coj mus kuaj:
Cov txiaj ntsig = [(BV) × N × F × 100]/W
B = 1 N sulfuric acid VS noj los ntawm Blank (mL)
V = 1 N sulfuric acid VS noj los ntawm Sample (mL)
N = qhov tseeb normality ntawm Back titrant (mEq/mL)
F = equivalency factor, 66.07 mg/mEq
W = qhov hnyav ntawm tus qauv (mg)
Kev lees txais: 99.0% -100.5%
IMPURITIES
• Residue ntawm Ignition <281>
Qauv: 20 g
Kev lees txais: NMT 0.005%
• Limit of Insoluble Matter
Qauv: 20 g
Kev Ntsuam Xyuas: Hloov cov qauv mus rau lub hau npog, thiab yaj hauv 200 mL dej.Tshav kub kom npau, thiab sov rau ntawm chav da dej rau 1 teev.Lim cov tshuaj kub los ntawm tared sintered-iav crucible ntawm nruab nrab porosity (10-15 µm).Ntxuav lub beaker thiab lim nrog dej kub, qhuav lub crucible ntawm 105, txias nyob rau hauv ib tug desiccator, thiab hnyav.
Kev lees txais: NMT 1 mg ntawm cov teeb meem insoluble pom (0.005%).
• Txwv ntawm Phosphate
Standard phosphate tov, Phosphate reagent A, thiab Phosphate reagent B: Npaj raws li qhia rau Phosphate nyob rau hauv Reagents nyob rau hauv Reagents, Indicators, thiab Solutions—Kev ntsuam xyuas dav dav rau Reagents.
Qauv: 4.0g
Tswj: 0.2 mL ntawm Standard phosphate tov
Kev tsom xam
[Ceeb Toom-Cov kev ntsuam xyuas rau Cov Qauv thiab Kev Tswj Xyuas yog ua kom zoo dua nyob rau hauv cov xim sib piv cov raj.]
Dissolve cov qauv hauv 25 mL ntawm 0.5 N sulfuric acid, ntxiv 1 mL txhua ntawm Phosphate reagent A thiab Phosphate reagent B, thiab tso cai rau sawv ntawm chav tsev kub rau 2 h.Ua raws li Kev Tswj Xyuas uas siv tib qhov ntau ntawm tib cov reagents ib yam li hauv kev sim rau Cov Qauv.
Kev lees txais cov qauv: Txhua xim xiav tau los ntawm Cov Qauv yuav tsum tsis txhob tshaj qhov uas tsim los ntawm Kev Tswj (NMT 5 ppm).
• Chloride thiab Sulfate, Chloride <221>
Standard chloride tov: Hloov 165 mg ntawm sodium chloride mus rau 100-mL volumetric hwj.Dissolve nyob rau hauv thiab dilute nrog dej rau ntim.Hloov 10.0 mL mus rau 1000-mL volumetric hwj, thiab dilute nrog dej mus rau ntim kom tau cov tshuaj uas muaj ib tug concentration ntawm 10 μg / mL ntawm chloride.
Kev lees txais: Ib feem 2-g qhia tias tsis muaj cov tshuaj chloride ntau dua li 1.0 mL ntawm Standard chloride tov (NMT 5 ppm).
• Txwv ntawm nitrate
Txheem nitrate tov thiab Brucine sulfate tov: Npaj raws li qhia rau Nitrate nyob rau hauv Reagents nyob rau hauv Reagents, Indicators, thiab Solutions-General Tests rau Reagents.
Piv txwv li: Dissolve 1.0 g nyob rau hauv 3 mL dej los ntawm cua sov nyob rau hauv lub boiling dej da dej, thiab ntxiv Brucine sulfate tov ua 50 mL.
Kev tswj cov tshuaj: Rau 1.0 mL ntawm Standard nitrate tov ntxiv 1.0 g ntawm ammonium nitrate, ces ntxiv Brucine sulfate tov ua 50 mL.
Tsis muaj: 50 mL ntawm Brucine sulfate tov
Kev Ntsuam Xyuas: Ua kom sov cov qauv kev daws teeb meem, tswj kev daws teeb meem, thiab khoob hauv cov dej kub npau npau rau 15 feeb nrog lub sij hawm maj mam swirling, ces txias sai sai hauv dej khov rau hauv chav sov.Kho qhov haum spectrophotometer nrog Blank rau xoom absorbance ntawm 410 nm.Txiav txim siab qhov absorbance ntawm Sample tov, nco ntsoov qhov tshwm sim, thiab kho cov cuab yeej nrog cov Sample tov rau xoom absorbance.Txiav txim siab qhov absorbance ntawm kev tswj kev daws teeb meem.
Kev lees txais cov qauv: Kev nyeem ntawv nqus rau cov qauv kev daws teeb meem tsis dhau qhov ntawd rau Kev Tswj Kev daws teeb meem (NMT 10 ppm).
• Hlau <241>
Piv txwv li: Dissolve 2.0 g hauv 40 mL dej, thiab ntxiv 2 mL ntawm hydrochloric acid.
Kev lees txais: NMT 5 ppm
TSEEM CEEB
• Kev Ntsuas Microbial Enumeration <61> thiab Kev Ntsuas rau Cov Kabmob Tshwj Xeeb <62>: Tag nrho cov aerobic microbial suav tsis pub tshaj 1000 cfu/g, thiab tag nrho cov pwm ua ke thiab cov poov xab suav tsis pub tshaj 10 cfu/g.
• pH <791>: 5.0-6.0 hauv cov kua (1 hauv 20)
TSEEM CEEB
• Ntim thiab Cia: Khaws rau hauv cov thawv kaw kom zoo.Tsis muaj qhov yuav tsum tau khaws cia.