235 Results for: "merck indicators"

Supplier: Merck

Chemizorb Hydrofluoric Acid (HF) is a powder mixture consisting of a synthetic copolymer as the absorbent, a calcium salt as a neutraliser and precipitant, and a pH indicator.

Supplier: Merck

Desiccant suitable for desiccators to remove water, and for drying most gases and liquids (apart from strongly acidic and basic gases, organic solvents or alkaline liquids). The product contains iron salts as the indicator. Colour change is from orange to colourless at approx. 7/10 g adsorbed H₂O/100 g silica gel. Regeneration can be performed as often as required at 130 to 140 °C in a drying oven for approx. 3 hours.

Supplier: Merck

Unmodified and modified cellulose plates for the analysis of polar substances.

Supplier: Merck

TLC plates, unmodified silica gel 60
Merck silica gel 60 has a unique polymeric binder that results in a uniform, hard surface that will not easily crack or blister. This smooth, extremely dense plate coating ensures narrow bands and maximum separation efficiency with the lowest background noise. Layer thickness 250 μm and particle size of 10 to 12 µm. Two inorganic fluorescent indicators for UV detection of colourless substances.

Supplier: Merck

Bromothymol blue sodium salt, water soluble indicator, Supelco®

Supplier: Merck

Thin-layer chromatography plates (TLC), TLC, MS-grade, Coating material: Silica gel, Backing material: Aluminium, Fluorescent indicator: F254, Plate size: 50×75 mm, Layer thickness: 100 µm, Pore size: 60 Å

Supplier: Merck

Application note: Method A or Method B
Method A: For the measurement the method 195, which is pre-calibrated in the Spectroquant® Pharo-and NOVA-photometers can be used. To increase the precision of the results a self-made blank according to the application is recommended generally.
Method B: For the measurement the pre-calibrated method 195 is not applicable. Instead of that, a self-made calibration according the application is to perform.

Supplier: Merck

Cyanide (free), Supelco®, Contents: KCN in H₂O, Application: Ion chromatography standards

Supplier: Merck

Refractive index standards traceable to SRM from NIST and PTB.

Supplier: Merck

Highly robust plates with gypsum as binder, fully compliant with international pharmacopoeia (Ph. Eur. and USP).

Supplier: SIGMA ALDRICH MICROSCOPY

Pyrocatechol Violet (PV) is a sulfone phthalein dye. It chelates metal ions. The metal-PV complex is bluish-violet in colour.

Supplier: Merck

Chromate standard solution, 1000 mg/L, Certipur®, Supelco®, Contents: K₂CrO₄ in H₂O

Supplier: Merck

Free fatty acids present in an oil or fat sample react with a pH indicator, the colour of which changes depending on the concentration of the free fatty acids. The concentration of the free fatty acids is measured semiquantitatively by visual comparison of the reaction zone of the test strip with the fields of a colour scale. The units of measurement are milligrams of KOH necessary to neutralise the free fatty acids in 1 g of fat sample.

Supplier: Merck

Cyanide standard solution, 1000 mg/L, Certipur®, Supelco®, Contents: K₂[Zn(CN)₄] in H₂O

Supplier: Merck

HPTLC plates, unmodified silica gel 60
This range of plates uses an optimised Merck silica gel 60 with a particle size of only 5 to 6 µm, which results in higher packing density and a smoother surface, therefore, reducing band diffusion. Less sample is required, 0,1 to 0,5 µl than for classic TLC.

Supplier: Merck

TLC plates, unmodified silica gel 60
This range of plates uses Merck silica gel 60 with a unique polymeric binder that results in a uniform, hard surface that will not easily crack or blister. The smooth, extremely dense plate coating ensures narrow bands and maximum separation efficiency with the lowest background noise. Layer thickness 200 μm and, particle size of 10 to 12 µm. Flexible aluminium plates that can easily be cut to match individual separation requirements. Two inorganic fluorescent indicators for UV detection of colourless substances. Samples which absorb shortwave UV at 254 nm are detected due to fluorescence quenching.

Supplier: Merck

Nitrite standard solution, 40,0 mg/L NO₂-N, Supelco®, Contents: NaNO₂ in H₂O, For test kit(s): 1.00609

Supplier: Merck

NaNO₃ in H₂O

Supplier: Merck

Nitrite standard solution, 1000 mg/L, Certipur®, Supelco®, Contents: NaNO₂ in H₂O, Application: Ion chromatography standards

Supplier: Merck

Merck Multiformat plates are pre-scored glass plates for easy breaking into various sizes. The plates use the same silica coating as the corresponding TLC or HPTLC plate delivering chromatograms that are identical to those of the non scored plates.

Supplier: Merck

Several reference materials for use in testing instruments are described in the European pharmacopoeias (e.g. Ph Eur. 2.2.6). In this case, the substances trimethylpentane, toluene and methylnaphthalene are prescribed. This instrument test should be carried out prior to every analysis. The comprehensive product range includes standards suitable for practically every operating range; the range 1,3915 to 1,6160 (20 °C) is covered.

Supplier: Merck

Kieselguhr is a natural diatomaceous earth that can be used for the separation of polar or moderately polar compounds. For the mixed layer plates a combination of classical silica gel 60 and kieselguhr is used, providing favorable properties for certain applications such as separations of inorganic ions, herbicides or steroids.

Supplier: Merck

Chloride standard solution, 1000 mg/L, Certipur®, Supelco®, Contents: NaCl in H₂O, Application: Ion chromatography standards

Supplier: Merck

This range of plates uses an optimised Merck silica gel 60 with a particle size of only 5 to 6 µm, which results in higher packing density and a smoother surface, therefore reducing band diffusion. Less sample is required, 0,1 to 0,5 µl than classic TLC.

Supplier: Merck

Phosphate standard solution, 1000 mg/L, Certipur®, Supelco®, Contents: KH₂PO₄ in H₂O, Application: Ion chromatography standards

Supplier: Merck

Fluoride standard solution, 1000 mg/L, Certipur®, Supelco®, Contents: NaF in H₂O, Application: Ion chromatography standards

Supplier: Merck

Fluoride standard solution, 1000 mg/l, Titrisol®, Supelco®, Contents: KF in H₂O, Application: Ion chromatography standards

Supplier: Merck

TLC plates, that feature a smooth and extremely dense plate coating, ensuring narrow bands and maximum separation efficiency with the lowest background noise. Flexible plastic sheets can easily be cut to match individual separation requirements.

Supplier: Merck

Nitrate standard solution, 1000 mg/L, Certipur®, Supelco®, Contents: NaNO₃ in H₂O, Application: Ion chromatography standards

Supplier: Merck

Kjeldahl catalyst acc. to Wieninger, Contents: >94% Na₂SO₄; >1,45% CuSO₄; >1,5% Se