NIeT-124_2025

Description of Products / Chemicals/ Glassgoods/Laboratory Articles

Chemicals:- Potassium dihydrogen phosphate : [104873 Supelco] Specifications : Traceable to the International Organization for Standardization (ISO) standard 6353; Assay- ≥99.5% dry basis (alkalimetric), 99.5-100.5% (alkalimetric); solubility-208 g/L; Quality Level-300; anion traces-chloride (Cl-): ≤0.0005%, sulfate (SO42-): ≤0.003%; pH-4.2-4.6 (20 °C, 20 g/L in H2O) (EMSURE®) (MERCK/SIGMA ALDRICH)

Phosphate standard solution certified reference material, 1000 mg/L (PO4),[1.04690 Supelco] Specifications : traceable to SRM from NIST KH₂PO₄ in H2O, Certipur; Quality Level-300; density-0.998 g/cm3 at 20 °C (EMSURE®)(MERCK/SIGMA ALDRICH)

Potassium standard solution [170230 Supelco] Specifications : traceable to SRM from NIST KNO₃ in HNO₃ 0.5 mol/l 1000 mg/l K Certipur®; Quality Level-300; density-1.013 g/cm3 at 20 °C; pH value- 0.5 (H₂O, 20 °C) (EMSURE®) (MERCK/SIGMA ALDRICH)

Ammonium chloride [101145 Supelco] for analysis EMSURE® ACS,ISO,Reag. Ph Eur. Specifications : Quality Level-300; Density- 1.53 g/cm3 (25 °C); pH- 5 - 5.5 (H₂O, 25 °C) (External MSDS); BD-600 - 900 kg/m3; Solubility- 372 g/l (External MSDS) (EMSURE®) (MERCK/SIGMA ALDRICH)

Urea [NIST2141] NIST® SRM® 2141 Specifications : grade-certified reference material; mp-132-135 °C (lit.); form-crystals (MERCK/SIGMA ALDRICH)

NIST999C Potassium Chloride Primary Standard (NIST)

Acetone for analysis [1.00014 Supelco ] Specifications : grade-ACS, ISO, Reag. Ph Eur; Assay- ≥99.8% (GC); density-0.790-0.793 g/cm3 at 20 °C; grade-ACS reagent (EMSURE®) (MERCK/SIGMA ALDRICH)

Nitric acid 65% [100456 Supelco] Specifications : Grade- Eur,ISO ; Quality Level-300; Density- 1.39 g/cm3 (20 °C); pH value- <1 (H₂O, 20 °C) strongly acid (EMSURE®) (MERCK/SIGMA ALDRICH)

Citric acid monohydrate (100244 Supelco ) Specifications : Grade- for analysis ACS,ISO,Reag. Ph Eur; Quality Level-300; Density- 1.54 g/cm3 (20 °C); pH value- 1.8 (50 g/l, H₂O, 20 °C) ; strongly acid; Solubility- 880 g/l; (EMSURE®) (MERCK/SIGMA ALDRICH)

Sodium molybdate dehydrate (106521 Supelco) Specifications : Grade: ACS,Reag. Ph Eur; Quality Level-300; Density- 2.71 g/cm3 (22 °C) (for the dihydrate); Mp- 687 °C Elimination of water of crystallization; pH- 9 - 10 (840 g/l, H₂O, 20 °C); BD- 1000 - 1400 kg/m3 (EMSURE®) (MERCK/SIGMA ALDRICH)

Synthetic Quinoline analytical standard (94517 Supelco) Specifications : Titration (NT) HCLO4 0.1M- 97.5 - 102.5 %; PURITY (GC AREA %)- ≥ 98.0 %; (SIGMA) (MERCK/SIGMA ALDRICH)

Sodium hydroxide pellets for analysis (1.06498 Supelco) Specifications : Traceable to NIST standards; Assay- ≥99% NaOH basis (acidimetric); impurities - ≤0.0003% Total nitrogen (N); pH- >14 (20 °C, 100 g/L in H2O); mp- 318 °C (lit.); Quality Level-300; Assay- ≥99% NaOH basis (acidimetric). (EMSURE®) (MERCK/SIGMA ALDRICH)

Hydrochloric acid solution (Titripur) (1.09060 Supelco) c(HCl) = 0.1 mol/l (0.1 N), Specifications : Grade -:reag. Ph. Eur., reag. USP, volumetric solution for titration; Quality Level -200; quality ; Quality -Analyzed in ourISO 17025 accredited QC lab; (TITRIPUR®) (MERCK/SIGMA ALDRICH)

Sodium hydroxide solution (1.09141 Supelco) (Titripur) c(NaOH) = 0.1 mol/l (0.1 N), Specifications : Grade -:reag. Ph. Eur., reag. USP, volumetric solution for titration; Quality Level -200; quality ; Quality -Analyzed in ourISO 17025 accredited QC lab; (TITRIPUR®) (MERCK/SIGMA ALDRICH)

Sulphuric Acid solution (1.09074 Titripur) c(H2SO4) = 0.1 mol/l (0.1 N), Specifications : Grade -:reag. Ph. Eur., reag. USP, volumetric solution for titration; Quality Level -200; quality ; Quality -Analyzed in ourISO 17025 accredited QC lab; (TITRIPUR®) (MERCK/SIGMA ALDRICH)

Hydrochloric acid (30721 Sigma-Aldrich) Specifications : ≥37%, puriss. p.a., ACS reagent, reag. ISO, reag. Ph. Eur., fuming, APHA: ≤10 (SIGMA) (MERCK/SIGMA ALDRICH)

Silica gel beads, desiccant ~ 2 - 5 mm; [1.07735.1000] Specifications - Quality Level -200; (MERCK) (MERCK/SIGMA ALDRICH)

Sulfuric acid 95-97% (100732 Supelco) Specifications :Grade-ACS,ISO,Reag. Ph Eur; Density-1.84 g/cm3 (20 °C); pH-0.3 (49 g/l, H₂O, 25 °C); VP-0.0001 hPa (20 °C); MP--20. 0°C); Quality Level-300 (EMSURE®) (MERCK/SIGMA ALDRICH)

Potassium sulfate (105153 Supelco) Specifications- for analysis EMSURE® ACS,ISO,Reag. Ph Eur; Quality Level-300; Density- 2.662 g/cm3 (20 °C); pH- 7 (H₂O, 25 °C); MP- 1067 °C; solubility- 111 g/l (EMSURE®) (MERCK/SIGMA ALDRICH)

Copper(II) sulfate (451657 Sigma-Aldrich) Specifications- anhydrous, powder, ≥99.99% trace metals basis - £100.0 ppm; (SIGMA) (MERCK/SIGMA ALDRICH)

Zinc powder for analysis particle size < 45 µm (108789 Supelco) Quality Level-300; Density- 7.140 g/cm3 (20 °C); pH- 7 (H₂O, 25 °C); VP- 1.33 hPa (487 °C); MP- 411 °C; solubility- 111 g/l; BD- 1800 - 2700 kg/m3 (EMSURE®) (MERCK/SIGMA ALDRICH)

Sodium tetraphenyl borate (106669 Supelco) Specifications Grade - GR for analysis ACS,Reag. Ph Eur; MP- >300 °C; pH- 8 (50 g/l, H₂O, 20 °C); BD- 500 kg/m3 (GR) (MERCK/SIGMA ALDRICH)

Benzalkonium chloride solution ≥50% (via Cl), 50% in H2O (63249 Sigma-Aldrich) Specifications: Quality Level- (SIGMA) (MERCK/SIGMA ALDRICH)

Formaldehyde solution 37 wt. % in H₂O, solution (252549 Sigma-Aldrich) Specifications-Grade-ACS reagent grade,contains 10-15% methanol as stabilizer (to prevent polymerization); Color Test-£10 APHA; Titration by H2SO4-36.5 - 38.0 %; Titratable Acid (meq/g)- £ 0.006; Residue on ignition (Ash)- £ 0.006; (SIGMA) (EMSURE®) (MERCK/SIGMA ALDRICH)

Titan yellow (C.I. 19540) (1.01307 Supelco) Specifications-Grade-metal indicator, Reag. Ph Eur; Quality Level-200; loss- ≤8% loss on drying, 110°C; MP- >300 °C (decomposition); pH- 5.1 (20 °C, 10 g/L in H2O), 20 °C); BD- 310 kg/m3; λmax- 398-402 nm (buffer pH 7.0); solubility- 29 g/L (MERCK) (EMSURE®) (MERCK/SIGMA ALDRICH)

Methyl Red (250198 Sigma-Aldrich) Specifications-Grade- ACS reagent; Melting Point 179 - 182 °C;Infrared spectrum Conforms to Structure; Solubility (Turbidity)-Pass 0.1%, Ethanol Clear Solution With Only A Faint Trace of Turbidity or Insoluble Matter Visual Interval 0Pass; pH 4.2 = Pink; Visual Interval-Pass; pH 5.5 = Orange Visual Interval- Pass pH 6.2 = Yellow (SIGMA) (MERCK/SIGMA ALDRICH)

Methylcarbinol/Ethanol absolute for analysis (1.00983 Supelco) Specifications-Grade- ACS,ISO,Reag. Ph Eur; Assay: ≥99.9% (GC); Bp:-78 °C (lit.);Vapor pressure:-59 hPa( 20 °C) (EMSURE®) (MERCK/SIGMA ALDRICH)

Boric acid for analysis (1.00165 Supelco) Specifications-Grade- ACS,ISO,Reag. Ph Eur; Assay- 99.5-100.5% (alkalimetric); Quality level-300; Vapor pressure:- 2.6 mmHg ( 20 °C); pH- 3.8-4.8 (20 °C, 33 g/L in H2O) (EMSURE®) (MERCK/SIGMA ALDRICH)

di-Ammonium hydrogen phosphate (1.01207 Supelco) Specifications-Grade- ACS, ISO,Reag. Ph Eur; Assay- ≥99.0% (acidimetric); Quality level-300; impurities- ≤0.005% Insoluble matter; pH- 7.6-8.2 (20 °C, 100 g/L in H2O); solubility-690 g/L (EMSURE®) (MERCK/SIGMA ALDRICH)

Potassium hydrogen phthalate Volumetric standard, secondary reference material for alkalimetry, (102400 Supelco) Specifications-Grade- traceable to NIST Standard Reference Material (SRM) Certipur® Reag. Ph Eu. Quality level-300; Mp- 301.7 °C; pH- 4.0 (50 g/l, H₂O, 20 °C); BD- 900 kg/m3; solubility-80 g/L (MERCK) (MERCK/SIGMA ALDRICH)

Ammonia solution 25%, for analysis (1.05423 Supelco) Specifications-Grade- ISO,Reag. Ph Eur; Quality level-300; Mp- -57.5 °C; pH- 4.0 (50 g/l, H₂O, 20 °C); Bp- 37.7 °C/1013 hPa;Density- 0.9 g/mL at 25 °C (lit.); Vp- 483 hPa ( 20 °C); expl. lim.- 27 % (EMSURE®) (MERCK/SIGMA ALDRICH)

Magnesium oxide for analysis (105865 Supelco) Specifications - Assay:≥97% (complexometric); Quality Level -300; impurities-≤0.1% Substances insoluble in hydrochloric acid, ≤0.5% Substances soluble in water; pH- 10.3 (20 °C in H2O, saturated solution); bp-3600 °C/1000 hPa; mp-2800 °C; density-3.58 g/cm3 at 25 °C (EMSURE®) (MERCK/SIGMA ALDRICH)

Citric acid/sodium hydroxide/hydrogen chloride ) pH 4.00 (25°C) [[1990640001] Specifications- Grade- traceable to SRM from NIST and PTB; Quality level-300; pH- 4.0 (25 °C in H2O); density- 1.01 g/cm3 at 20 °C (Certipur®) (MERCK/ SIGMA ALDRICH)

Potassium dihydrogen phosphate/di-sodium hydrogen phosphate Buffer solution pH(S) = 7.0 (25°C) [1.99002 Supelco], Specifications- Grade-directly traceable to primary SRM from NIST/PTB; Quality level-300; pH- 7.0 (25 °C in H2O); bp- 109 °C/1013 hPa; mp- -5 °C; density- 1.01 g/cm3 at 20 °C (Certipur®) (MERCK/SIGMA ALDRICH)

Di-sodium tetraborate decahydrate pH 9.18 (25°C) [107203 Supelco], Specifications- Grade- primary SRM from NIST/PTB; Quality level-300; pH- 9.2 (H₂O, 25 °C); bp- 100 °C (1013 hPa); density- 1.00 g/cm3 (20 °C) (Certipur®) (MERCK/SIGMA ALDRICH)

Salicylic acid for synthesis (818731 Sigma-Aldrich) Specifications- Quality level-200; Mp- 158 - 160 °C; pH- 2.4 (H₂O, 20 °C) (saturated solution); Bp- 211 °C (1013 hPa);Density- 1.44 g/cm3 (20 °C); Vp- 1 hPa (114 °C); Solubility- 2 g/l, BD- 400 - 500 kg/m3 (SIGMA) (MERCK/SIGMA ALDRICH)

Sodium thiosulfate anhydrous (106512 Supelco) Specifications- Quality level-200; Mp- 48 °C; pH- 6.0 - 9.5 (50 g/l, H₂O, 20 °C); Bp- 211 °C (1013 hPa);Density- 1.667 g/cm3 (20 °C); Solubility- 701 g/l, BD- 1350 kg/m3 (EMPLURA®) (MERCK/SIGMA ALDRICH)

Chromium ≥99% trace metals basis, powder, <45 μm (266299 Sigma-Aldrich) Specifications- Quality Level-100; resistivity-12.7 μΩ-cm, 20°C; bp-2672 °C (lit.); mp-1857 °C (lit.); density-7.14 g/mL at 25 °C (lit.) (SIGMA) (MERCK/SIGMA ALDRICH)

Iron(II) sulfate heptahydrate for Analysis (103965 Supelco) Specifications- Grade- ACS,ISO,Reag. Ph Eur ; Quality Level-100; Molar Mass-278.01 g/mol;pH-3.0 - 4.0 (50 g/l, H₂O, 25 °C), VP-14.6 hPa (25 °C); bp-2672 °C (lit.); mp-64 °C Elimination of water of crystallisatio; density-1.898 g/cm3 (25 °C); BD-600 kg/m3, Solubility -400 g/l (EMPLURA®) (MERCK/SIGMA ALDRICH)

Barium chloride dehydrate (101719 Supelco) Specifications- Grade- ACS,ISO,Reag. Ph Eur; Molar mass- 244.28 g/mol; Density-3.100 g/cm3 (18 - 25 °C); Melting Point- 113 °C (anhydrous substance); pH value-5.0 - 8.0 (50 g/l, H₂O, 25 °C); Bulk density- 1200 - 1400 kg/m3 (EMSURE®) (MERCK/SIGMA ALDRICH)

Sodium carbonate anhydrous (102405 Supelco) Specifications- Grade- volumetric standard, secondary reference material for acidimetry, traceable to NIST SRM; Molar mass- 105.99 g/mol; Boiling point-1600 °C (decomposition); Density-2.52 - 2.53 g/cm3 (20 °C);Melting Point-851 °C; pH value-11.16 (4 g/l, H₂O, 25 °C);Bulk density-1100 kg/m3;Solubility-212.5 g/l (Certipur®) (MERCK/SIGMA ALDRICH)

Silver nitrate for analysis (101512 Supelco)Specifications- Grade- ACS,ISO,Reag. Ph Eur; Molar mass- 169.87 g/mol; Quality level-300; Boiling point- 444 °C (1013 hPa) (decomposition); Density-4.350 g/cm3;Melting Point-212 °C; pH value-5.4 - 6.4 (100 g/l, H₂O, 20 °C);Bulk density-2350 kg/m3; Solubility-2160 g/l (EMSURE®) (MERCK/SIGMA ALDRICH)

Potassium sodium tartrate tetrahydrate for analysis (108087 Supelco) Specifications- Grade-ACS,ISO,Reag. Ph Eur; Quality level-300; Molar mass- 282.23 g/mol; Quality level-300; Melting Point -70 - 80 °C; pH value-7.0 - 8.5 (H₂O); Bulk density-1000 kg/m3; Solubility-630 g/l. (EMSURE®) (MERCK/SIGMA ALDRICH)

Biuret 98% (Contains ≤10%(w/w) Triuret) (15270 Sigma-Aldrich) Specifications- Molecular Weight-103.08; Quality Level -100; Assay-98% (Contains ≤10%(w/w) Triuret); impurities-≤1% water; mp-185-190 °C (dec.) (lit.) (SIGMA)(MERCK/SIGMA ALDRICH)

Calcium carbonate volumetric standard, secondary reference material for complexometry (102410 Supelco) Specifications-Grade- NIST Standard Reference Material (SRM) USP; Molecular Weight-100.09 g/mol; Quality Level -300; Density-2.8 g/cm3; Melting Point-825 °C (decomposition); pH value-8.0 (H₂O) (slurry); Bulk density-300 - 1400 kg/m3; Solubility-0.017 g/l (Certipur®) (MERCK/SIGMA ALDRICH)

Ethylenedinitrilotetraacetic acid disodium salt dihydrate (1.08454 Supelco) Specifications-Grade- ESSENTIAL, Ph. Eur., BP, ChP, JP, USP; Molecular Weight-327.24 g/mol; Quality Level -100; pH- 4-5 (20 °C, 50 g/L in H2O); mp-248 °C (dec.) (lit.); solubility-100 g/L; bulk density-700 kg/m3 (MERCK)(MERCK/SIGMA ALDRICH)

Magnesium sulfate heptahydrate for analysis (1.93245 Supelco) Specifications-Grade- ACS; Molecular Weight-246.47 g/mol; Quality level-200; vapor density-<0.01 (vs air); vapor pressure-<0.1 mmHg ( 20 °C) ( EMPARTA®) (MERCK/SIGMA ALDRICH)

Eriochrome black T (C.I. 14645) (103170 Supelco) Specifications-Grade- ACS,Reag. Ph Eu; Molecular Weight- 461.38 g/mol ; Quality Level -200; Absorption maximum λmax. (buffer pH 10.0) -612 - 616 nm; Spec. Absorptivity A 1%/1cm (λmax; 0.02 g/l; buffer pH 10.0; calc. on dried substance)-400 – 510; Loss on drying (110 °C)-≤ 7 % (MERCK) (MERCK/SIGMA ALDRICH)

Ammonium iron(II) sulfate hexahydrate (215406 Sigma-Aldrich) Specifications-Grade- ACS, Molecular Weight- 392.14g/mol ; Quality Level -200; Assay-98.5-101.5%; 99%;impurities-≤0.01% insolubles; ≤0.05% Not NH4OH pptd.; pH-3-5 (20 °C, 50 g/L); mp-100 °C (dec.) (lit.) (SIGMA) (MERCK/SIGMA ALDRICH)

Ammonium thiocyanate (101213 Supelco) Specifications-Grade-ACS, ISO,Reag. Ph Eur; Molecular Weight- 76.12g/mol ; Quality Level -300; Density -1.31 g/cm3 (20 °C); Melting Point-152 - 154 °C; pH value-4.0 - 5.5 (76.1 g/l, H₂O, 25 °C); Vapor pressure-<0.1 hPa (20 °C); Bulk density-600 - 700 kg/m3; Solubility-1600 g/l (EMSURE®) (MERCK/SIGMA ALDRICH)

Benzene for analysis (1.01783.2500) Specification-Grade ACS, ISO, Reag. Ph Eur; purity-≥99.7%, mp-≥5.2ºC, Bp-79-81ºC; Density-0.877-0.879 g/cm3 (d 20º C/4º C) (EMSURE®) (MERCK/SIGMA ALDRICH)

Ammonium nitrate for analysis (101188 Supelco) Specification-Grade-ACS, Mol. Mass-80.04g/mol; Quality Level -300; Boiling point-210 °C (15.0 hPa); Density-1.725 g/cm3 (25 °C); Melting Point-169 °C; pH value-4.5 - 7.0 (100 g/l, H₂O, 20 °C);Bulk density-600 - 700 kg/m3;Solubility-1920 g/l (EMSURE®) (MERCK/SIGMA ALDRICH)

Bromothymol blue (103026 Supelco) Specifications- Grade- ACS,Reag. Ph Eur ; Molecular Weight- 624.40 g/mol; Quality Level -200; Melting point-201 °C; BD-450kg/m3; Transition range-pH 5.8 - pH 7.6 yellow – blue; Absorption maximum λ 1 max. (buffer pH 5.8) -430 - 435 nm; Absorption maximum λ 2 max. (buffer pH 7.6)-615 - 618 nm; Spec. Absorptivity A 1%/1cm (λ 1 max.; 0.005 g/l; buffer pH 5.8; calc. on dried substances)-260 - 305 (MERCK) (MERCK/SIGMA ALDRICH)

Phenolphthalein (107233 Supelco) Specifications-Grade- ACS,Reag. Ph Eur; Molecular Weight- 318.33 g/mol; Quality Level -200; Density -1.27 g/cm3 (32 °C); Melting Point-263.7 °C; Vapor pressure-<0.1 hPa (50 °C); Bulk density-350 - 450 kg/m3; Solubility-3.36 mg/l (MERCK) (MERCK/SIGMA ALDRICH)

Sulfur (414980 Sigma-Aldrich) Specifications- 99.98% trace metals basis; Molecular Weight- 32.07 g/mol; Assay-99.98% trace metals basis; Trace Metal Analysis < 250.0 ppm (SIGMA) (MERCK/SIGMA ALDRICH)

Ammonium iron(III) citrate (103762 SAFC) Specifications-Quality level-200; Density-1.064 g/cm3 (978 hPa, 26 °C): pH value -6 - 8 (100 g/l, H₂O, 20 °C); Solubility-1200 g/l (EMPARTA®) (MERCK/SIGMA ALDRICH)

Calcon metal indicator Specifications-Absorption maximum ʎmax (Ethanol) : 569-572nm, Spec. Absorptivity A 1%/1cm (ʎmax: 0.025g/l ; ethanol; calc, on water free substance) ≥ 250, Water (according to Karl Fischer )≤ 9 (EMPARTA®) (MERCK/SIGMA ALDRICH)

Carbon disulfide (102214 Supelco) Specifications-Grade- Reag. Ph Eur, Molecular Weight- 76.14 g/mol; Quality Level -300; Boiling point-46.5 °C (1013 hPa); Density-1.26 g/cm3 (20 °C); Explosion limit-1 - 60 %(V);Flash point--30 °C; Ignition temperature-95 °C; Melting Point--111.5 °C; Vapor pressure-274 hPa (25 °C);Solubility- 2.1 g/l (EMPARTA®) (MERCK/SIGMA ALDRICH)

Barium hydroxide octahydrate for analysis Specifications- Grade- ACS,ISO,Reag. Ph Eur: Quality Level-100; Molar Mass-315.48 g/mole; pH-12.5 (50 g/l, H₂O, 20 °C) (saturated aqueous solution), mp-78°C; density-2.180 g/cm3; BD-900 - 1100 kg/m3, Solubility -72 g/l. (EMPARTA®) (MERCK/SIGMA ALDRICH)

D(-)-Mannitol (105983 Supelco) Specifications- Quality Level-100; Molar Mass-182.17 g/mol; Boiling point-290 - 295 °C (4 hPa); Density-1.52 g/cm3 (20 °C); Ignition temperature-410 °C; Melting Point-165 °C; pH value- 5.0 - 6.5 (182 g/l, H₂O, 25 °C); Bulk density-400 - 500 kg/m3;Solubility-213 g/l (MERCK) (MERCK/SIGMA ALDRICH)

Bismuth (III) nitrate (101878 Supelco) alkaline for analysis Specifications- Grade- Reag. Ph Eur; Quality Level-300; Molar Mass- 1461.99 g/mole; Density-4.93 g/cm3; Melting Point-500 °C Not applicable,(decomposition); pH value-3.2 (50 g/l, H₂O, 20 °C) (slurry); Bulk density-600 kg/m3 (EMSURE®) (MERCK/SIGMA ALDRICH)

Sodium diethyldithiocarbamate trihydrate (106689 Supelco) Specifications- Grade-ACS; Quality Level-100; Molar Mass- 225.31g/mole; Melting Point-93 °C; pH value-7 (20 g/l, H₂O, 20 °C); Solubility-600 g/l (MERCK) (MERCK/SIGMA ALDRICH)

Carbon tetrachloride reagent grade, 99.9% (319961 Sigma-Aldrich) Specifications- Assay-99.9%; Bp-76-77 °C (lit.); Vapor pressure-143 mmHg ( 30 °C); 91 mmHg ( 20 °C) (SIGMA) (MERCK/SIGMA ALDRICH)

Potassium permanganate (105082 Supelco) Specifications- Grade: ACS,Reag. Ph Eur; Molar Mass- 158.03 g/mole; Quality Level-300; Density -2.70 g/cm3 (20 °C); Melting Point->240 °C (decomposition); pH value-7 - 9 (20 g/l, H₂O, 20 °C); Vapor pressure-<0.01 hPa (20 °C); Bulk density-1300 - 1600 kg/m3; Solubility-64 g/l (EMSURE®) (MERCK/SIGMA ALDRICH)

Ortho-Phosphoric acid 85% (100573 Supelco) Specifications- Grade: ACS,ISO,Reag. Ph Eur; Quality Level-300; Boiling point- 158 °C (1013 mbar); Density-;1.71 g/cm3 (20 °C); Melting Point-21 °C; pH value-0.5 (100 g/l, H₂O, 20 °C); Vapor pressure-2 hPa (20 °C); Viscosity kinematic- 30.5 mm2/s (20 °C) (EMSURE®) (MERCK/SIGMA ALDRICH)

Potassium thiocyanate (105125 Supelco) Specifications- Grade: ACS,ISO,Reag. Ph Eur; Molar Mass- 97.18 g/mole; Quality Level-300; Boiling point->400 °C (1013 hPa) Not applicable,(decomposition); Density-1.890 g/cm3 (20 °C); Melting Point-173 °C; pH value-5.3 - 8.7 (97.2 g/l, H₂O, 25 °C); Vapor pressure- <0.1 hPa (20 °C); Bulk density- 750 - 1000 kg/m3; Solubility->1000 g/l (EMSURE®) (MERCK/SIGMA ALDRICH)

Potassium chromate (104952 Supelco) Specifications- Grade: ACS,ISO,Reag. Ph Eur; Molar Mass- 194.2 g/mole; Quality Level-300; Density- 2.73 g/cm3; Melting Point- 968.3 °C; pH value- 8.5 - 10.0 (50 g/l, H₂O, 20 °C); Bulk density-1400 kg/m3; Solubility-637 g/l (EMSURE®) (MERCK/SIGMA ALDRICH)

Strontium chloride hexahydrate (107865 Supelco) Specifications- Grade: ACS; Molar Mass- 266.62 g/mole; Quality Level-300; Density- 1.95 g/cm3 (20 °C); Melting Point-61 °C; pH value-5 - 7 (50 g/l, H₂O, 25 °C); Bulk density-1050 kg/m3; Solubility-2058 g/l (EMSURE®) (MERCK/SIGMA ALDRICH)

Sulfate standard solution Na₂SO₄ in H₂O 1000 mg/l SO₄ (119813 Supelco) Specifications- Grade: traceable to SRM from NIST; Density- 0.998 g/cm3 (20 °C); (Certipur®) (MERCK/SIGMA ALDRICH)

Hydroxylamine hydrochloride (55460 Sigma-Aldrich) ≥99.0% (RT) Specifications- Grade- ACS; Formula Weight- 69,49 g/mol; PH of Solution (PH) 2.5 - 3.5 at 25º C, 50 mg/ml in H2O; Assay- ≥99.0% (RT) (Sigma) (MERCK/SIGMA ALDRICH)

Iso-Amyl alcohol (100979 Supelco) Specifications- Grade- ACS,Reag. Ph Eur; Molar mass-88.15g/mole; Density-0.81 g/cm3 (20 °C); Explosion limit-1.2 - 8 %(V); Flash point-43.5 °C; Ignition temperature-335 °C; Melting Point--147 °C; pH value-5.6 (25 g/l, H₂O, 20 °C); Saturation concentration (air)-11 g/m3 (20 °C) Air; Vapor pressure 3 hPa (20 °C); Viscosity kinematic-5.32 mm2/s (20 °C);Solubility-25 g/l (EMSURE®) (MERCK/SIGMA ALDRICH)

Triethanolamine (108379 Millipore) Specifications-Molar mass- 149.19 g/mol; Boiling point -360 °C (1013 hPa) (decomposition); Density-1.124 g/cm3 (20 °C); Explosion limit-3.6 - 7.2 %(V); Flash point-179 °C; Ignition temperature-325 °C DIN 51794; Melting Point-20.5 °C; pH value 10.5 - 11.5 (149 g/l, H₂O, 25 °C); Vapor pressure-<0.01 hPa (20 °C) (EMPARTA) (MERCK/SIGMA ALDRICH)

Zinc standard solution (AAS std)- 1000 ppm (119806 Supelco) Specifications- Metrological traceability: Directly traceable to NIST SRM 3168a, lot 120629, Certified value as mass fraction 10.007 mg/g ± 0.020 mg/g (Certipur®) (MERCK/SIGMA ALDRICH)

Iron standard solution (AAS std)- 1000 ppm (119781 Supelco) Specifications- Metrological traceability: Directly traceable to NIST SRM 3126a, lot 140812, Certified value as mass fraction 987 mg/kg, Associated uncertainty, U=k•u (k=2) as mass fraction ± 5mg/kg (Certipur®) (MERCK/SIGMA ALDRICH)

Manganese standard sol. (AAS std)- 1000 ppm (1.19789 Supelco) Specifications- Metrological traceability: Directly traceable to NIST SRM 3132, lot 050429, Certified value as mass fraction 986 mg/kg,Associated uncertainty, U=k•u (k=2) as mass fraction ± 5mg/kg (Certipur®) (MERCK/SIGMA ALDRICH)

Copper standard solution (AAS std)- 1000 ppm (119786 Supelco) Specifications-Metrological traceability: Directly traceable to NIST SRM 3114, lot 120618, Certified value as mass fraction 986 mg/kg, Associated uncertainty, U=k•u (k=2) as mass fraction ± 5mg/kg (Certipur®) (MERCK/SIGMA ALDRICH)

Boron standard solution(AAS std)- 1000 ppm (119500 Supelco) Specifications-Metrological traceability: Directly traceable to traceable to SRM from NIST (Certipur®) (MERCK/SIGMA ALDRICH)

Molybdenum standard solution (AAS std)- 1000 ppm (170227 Supelco) Specifications-Metrological traceability: Directly traceable to NIST SRM 3134, lot 130418, Certified value as mass fraction 1003 mg/kg, Associated uncertainty, U=k•u (k=2) as mass fraction ± 5mg/kg (Certipur®) (MERCK/SIGMA ALDRICH)

Calcium standard solution (AAS std)- 1000 ppm (119778 Supelco) Specifications-Metrological traceability: Directly traceable to NIST SRM 3109a, lot 130213, Certified value as mass fraction 9.819 mg/g ± 0.019 mg/g (Certipur®) (MERCK/SIGMA ALDRICH)

Magnesium standard solution (AAS std)- 1000 ppm (119788 Supelco) Specifications- Metrological traceability: Directly traceable to NIST SRM 3131,lot 140110, Certified value as mass fraction 982 mg/kg, (Certipur®) (MERCK/SIGMA ALDRICH)

Sodium standard solution (AAS std)- 1000 ppm (170238 Supelco) Specifications-Metrological traceability: Directly traceable to NIST SRM 3152a, lot 200413, Certified value as mass fraction 988 mg/kg,Associated uncertainty, U=k•u(k=2) as mass fraction ± 6 mg/kg (Certipur®) (MERCK/SIGMA ALDRICH)

Lead standard solution (AAS std)- 1000 ppm (1.19776 Supelco)Specifications-Metrological traceability: Directly traceable to NIST SRM 3128, lot 101026, Certified value as mass fraction 987 mg/kg, Associated uncertainty, U=k•u (k=2) as mass fraction ± 5mg/kg (Certipur®) (MERCK/SIGMA ALDRICH)

Cadmium standard solution (AAS std)- 1000 ppm (1.19777 Supelco)Specifications- Metrological traceability: Directly traceable to NIST SRM 3108, lot 130116, Certified value as mass fraction 984 mg/kg, Associated uncertainty, U=k·u (k=2) as mass fraction ± 5mg/kg (Certipur®) (MERCK/SIGMA ALDRICH)

Nickel standard solution (AAS std)- 1000 ppm (1.19792 Supelco) Specifications- Metrological traceability: Directly traceable to NIST SRM 3136, lot 120619, Certified value as mass fraction 988 mg/kg, Associated uncertainty, U=k·u (k=2) as mass fraction ± 5mg/kg (Certipur®) (MERCK/SIGMA ALDRICH)

Chromium standard solution (AAS std)- 1000 ppm: (119779 Supelco) Specifications- Metrological traceability: Directly traceable to NIST SRM 3112a, lot 170630, Certified value as mass fraction 990 mg/kg, Associated uncertainty, U=k•u (k=2) as mass fraction ± 5mg/kg (Certipur®) (MERCK/SIGMA ALDRICH)

Arsenic standard solution (AAS std)- 1000 ppm: (119773 Supelco) Specifications- Metrological traceability: Directly traceable to NIST SRM 3103a, lot 220201, Certified value as mass fraction 10.002 mg/g ± 0.024 mg/g (Certipur®) (MERCK/SIGMA ALDRICH)

Mercury standard solution (AAS std)- 1000 ppm (170226 Supelco)Specifications- Metrological traceability: Directly traceable to NIST SRM 3133, lot 160921, Certified value as mass fraction 948 mg/kg, Associated uncertainty, U=k•u (k=2) as mass fraction ± 8mg/kg (Certipur®) (MERCK/SIGMA ALDRICH)

Methanol for analysis (106008 SAFC) Specifications-Grade- Eur,BP,JPE,NF; Molar Mass-32.04 g/mol; Boiling point-64.5 °C (1013 hPa); Density- 0.792 g/cm3 (20 °C); Evaporation number-1.9; Explosion limit-5.5 - 44 %(V); Flash point-9.7 °C;Ignition temperature-420 °C DIN 51794; Melting Point--97.8 °C; Vapor pressure-128 hPa (20 °C);Viscosity kinematic-0.54 - 0.59 mm2/s (20 °C) no data available. (EMPROVE®) (MERCK/SIGMA ALDRICH)

Potassium hexacyanoferrate(II) trihydrate (104984 Supelco) Specifications-Grade-ACS,ISO,Reag. Ph Eur; Quality level-300; Molar Mass-422.39 g/mol; Density-1.85 g/cm3 (20 °C) (anhydrous substance); Melting Point-70 °C Elimination of water of crystallization; pH value-8.0 - 10 (211 g/l, H₂O, 25 °C) (anhydrous substance); Bulk density-950 -1050 kg/m3; Solubility-289 g/l (EMPROVE®) (MERCK/SIGMA ALDRICH)

Potassium hydroxidepellets for analysis (105033 Supelco) Specifications- Quality level-300; Molar Mass- 56.11 g/mol; Density-2.04 g/cm3 (20 °C); Melting Point-360 °C; pH value-13.5 (5.6 g/l, H₂O, 25 °C); Vapor pressure-1 hPa (719 °C); Solubility-1130 g/l (EMPROVE®) (MERCK/SIGMA ALDRICH)

Potassium chloride solution (nominal reference material for the measurement of electrolytic conductivity (c=0.01 mol/l) 1.01203.0500 (Certipur®) (MERCK/SIGMA ALDRICH)

Perchloric acid 70-72% (100519 Supelco) Specifications- Grade- ACS, ISO, Reag. Ph Eur; Quality level-300; Boiling point-198.7 °C (1013 hPa); Density-1.68 g/cm3 (20 °C); Melting Point- -18 °C (EMSURE®) (MERCK/SIGMA ALDRICH)

Potassium peroxodisulfate for analysis (<= 0.001% N) (105092 Supelco) Specifications- Grade- ACS, Reag. Ph Eur; Quality level-300; Density-2.477 g/cm3; Melting Point-100 °C (decomposition); pH value-2.5 - 4.5 (27 g/l, H₂O, 25 °C); Vapor pressure-<0.1 hPa (25 °C); Bulk density-1150 kg/m3; Solubility-50 g/ (EMSURE®) (MERCK/SIGMA ALDRICH)

Selenium powder, − 100 mesh, Specifications-Purity -99.99% trace metals basis (229865 Sigma-Aldrich); Molecular weight-78.96g/mol. (SIGMA) (MERCK/SIGMA ALDRICH)

Mercury(II) oxide red, for analysis (1.04466 Supelco) Specifications-Molecular Weight:216.59; Assay:≥99.0% (complexometric);Solubility:0.052 g/L (EMSURE®) (MERCK/SIGMA ALDRICH)

Extran® [1075531000] MA 02 liquid, neutral, concentrate 60755305001730 (MERCK) (MERCK/SIGMA ALDRICH)

Ammonium Standard Solution [1250230100] traceable to SRM from NIST1.00 mg/l NH₄-N in H₂O (MERCK) (MERCK/SIGMA ALDRICH)

Reduced iron powder, electrically reduced (Iron foundry)or ≥99%, powder (fine), reduced (MERCK) (MERCK/SIGMA ALDRICH)

Jack bean meal [12352204] [J0125] Specifications- Molecular Weight: 220 kDa1; pI: 6.2; Extinction Coefficient: E 1% = 11.4 (280 nm, 100 mM NaCl) 2pI: 4.5, 4.7, 5.1, 5.53 (SIGMA) (MERCK/SIGMA ALDRICH)

Methyl purple Indicator Solution 277339 Sigma-Aldrich; Specifications- Molecular Weight-1391.41 (SIGMA) (MERCK/SIGMA ALDRICH)

Sodium carbonate volumetric standard [1024050080], secondary reference material for acidimetry, traceable NIST SRM (Certipur®) (MERCK/SIGMA ALDRICH)

Sodium dodecyl benzene sulphate [515-42-4] Pharmaceutical Secondary Standard; Certified Reference Material (Certipur®) (MERCK/SIGMA ALDRICH)

Carbon tetrachloride anhydrous, ≥99.5% (289116 Sigma-Aldrich) Specifications-Molecular Weight:153.82; Assay:≥99.5%; Bp:76-77 °C (lit.); Vapor pressure:143 mmHg ( 30 °C); 91 mmHg ( 20 °C) (MERCK/SIGMA ALDRICH)

Carbon disulfide (1.02214 Supelco); Specifications-Grade-Reag. Ph Eur; Assay:≥99.9% (GC);Bp:46.5 °C/1013 hPa; Vapor pressure: 398 hPa ( 20 °C) (EMSURE®) (MERCK/SIGMA ALDRICH)

Glassgoods:- Beaker Heavy duty Low form (Borosil ®)

Beaker Heavy duty Low form (Borosil ®)

Beaker Heavy duty Low form (Borosil ®)

Beaker Heavy duty Low form (Borosil ®)

Beaker Heavy duty Low form (Borosil ®)

Measuring Cylinders, Graduated, with Hexagonal Base, Accuracy as per ASTM, Class A, With certificate Graduated, with Hexagonal Base (Borosil ®)

Measuring Cylinders, Graduated, with Hexagonal Base, Accuracy as per ASTM, Class A, With certificate Graduated, with Hexagonal Base (Borosil ®)

Measuring Cylinders, Graduated, with Hexagonal Base, Accuracy as per ASTM, Class A, With certificate Graduated, with Hexagonal Base (Borosil ®)

Measuring Cylinders, Graduated, with Hexagonal Base, Accuracy as per ASTM, Class A, With certificate Graduated, with Hexagonal Base (Borosil ®)

Measuring Cylinders, Graduated, with Hexagonal Base, Accuracy as per ASTM, Class A, With certificate Graduated, with Hexagonal Base (Borosil ®)

Measuring Cylinders, Graduated, with Hexagonal Base, Accuracy as per ASTM, Class A, With certificate Graduated, with Hexagonal Base (Borosil ®)

Measuring Cylinders, Graduated, with Hexagonal Base, Accuracy as per ASTM, Class A, With certificate Graduated, with Hexagonal Base (Borosil ®)

Volumetric Flasks with i/c Glass Stopper Accuracy as per Class A, USP (US pharmacopoeia), with Certificate (Borosil ®)

TUBE LIGHT (PHILIPS) ( 40 Watt.) (AS REQUIRED) (Per Piece) (Borosil ®)

Volumetric Flasks with i/c Glass Stopper Accuracy as per Class A, USP (US pharmacopoeia), with Certificate (Borosil ®)

Volumetric Flasks with i/c Glass Stopper Accuracy as per Class A, USP (US pharmacopoeia), with Certificate (Borosil ®)

Flat bottom Flask with Teflon screw cap (Borosil ®)

FUNNELS Plain 600 Angle, short stem (Borosil ®)

GLASSCO Silica Crucibles, (Glassco)

Standard Borosilicate Glass Gooch Crucible (Borosil ®)

Standard Keltube fitted for Pelican instruments (Palican)

Conical Flasks, Heavy Duty, Conical (Erlenmeyer) Narrow Mouth, (Borosil ®)

Conical Flasks, Heavy Duty, Conical (Erlenmeyer) Narrow Mouth, (Borosil ®)

Conical Flasks, Heavy Duty, Conical (Erlenmeyer) Narrow Mouth with stopper, ISO (Borosil ®)

Heavy duty Filtering Flask, Bolt Neck with Tubulation (Borosil ®)

Heavy PIPETTES Measuring (Serological Type), Accuracy as per Class A, with Certificate, ASTM 1293-02 NABL Certified (Borosil ®)

Heavy PIPETTES Measuring (Serological Type), Accuracy as per Class A, with Certificate, ASTM 1293-02 NABL Certified (Borosil ®)

Heavy PIPETTES Measuring (Serological Type), Accuracy as per Class A, with Certificate, ASTM 1293-02 NABL Certified (Borosil ®)

Heavy PIPETTES Measuring (Serological Type), Accuracy as per Class A, with Certificate, ASTM 1293-02 NABL Certified (Borosil ®)

Heavy PIPETTES Measuring (Serological Type), Accuracy as per Class A, with Certificate, ASTM 1293-02 NABL Certified (Borosil ®)

Pipettes, Transfer, Volumetric, Class A, ASTM E- 969 02 NABL Certified (Borosil ®)

Pipettes, Transfer, Volumetric, Class A, ASTM E-969-02 NABL Certified (Borosil ®)

Pipettes, Transfer, Volumetric, Class A, ASTM E-969-02 NABL Certified (Borosil ®)

Pipettes, Transfer, Volumetric, Class A, ASTM E-969-02 NABL Certified (Borosil ®)

Pipettes, Transfer, Volumetric, Class A, ASTM E-969-02 NABL Certified) (Borosil ®)

Pipettes, Transfer, Volumetric, Class A, ASTM E-969-02 NABL Certified (Borosil ®)

Burette with Straight Bore PTFE Key Stopcock, Class A (Borosil ®)

Burette with Straight Bore PTFE Key Stopcock, Class A (Borosil ®)

Walters Gooch Crucible Holder and Buckner Funnel holder (Optimus)

Laboratory Articles:- [WHA1001150] Whatman® qualitative filter paper, Grade 1 circles, pack of 100 (Sigma Aldrich)

[WHA1440150] Whatman® quantitative filter paper, ashless, Grade 40, pack of 100 (Sigma Aldrich)

Whatman 1441-150 41 Ashless Quantitative Filter Paper, 20-25um, 15cm; 100/Box (Cole Palmer)

[WHA1442150] Whatman® quantitative filter paper, ashless, Grade 42 (Sigma Aldrich)

[28462-126] Grade 5 qualitative filter paper standard grade, pack of 100 (Avantar VWR)

WHA10538018Whatman no.12 fluted filter paper Whatman qualitative filter paper, Grade CF 12. sheets, W × L 580 mm × 580 mm,pack of 100. (Sigma Aldrich)

Eppendorf Pipette dispenser/Seripator (Eppendorf)

Digital burette (Eppendorf)

Pipette controller (Variable volume) with Microtip (1000pcs) (Eppendorf)

Pipette controller (Variable volume) with Microtip (1000pcs) (Eppendorf)

Separating funnel with teflon screw adjustment (Borosil ®)

Vacuum desiccators (Borosil ®)

Vacuum desiccators with attachment to pump (Borosil ®)

Ruby Chemicals And Instruments (BID ID -7682617)

OPTIMUS INSTRUMENTS (BID ID -7683683)

KRISHNA SCIENTIFIC SUPPLIERS (BID ID -7685330)

GUHA SCIENTIFIC AGENCY