natgillin/translations-raw huggingface dataset:
Ledningsevnen udtrykkes i mikrosiemens pr. cm (µS cm-1) ved 20 °C uden decimaler for 25 % (m/m) (25° Brix) opløsningen af rektificeret koncentreret most.
The result is expressed in microsiemens per cm (µScm–1) at 20 °C to the nearest whole number for the 25 % (m/m) (25° Brix) solution of rectified concentrated must.
Metodernes princip
Principle of the methods
Kolorimetrisk metode
Colorimetric method
Furanforbindelser, hvoraf den vigtigste er hydroxymethylfurfural, reagerer som aldehyder med barbitursyre og paratoluidin og giver en rød forbindelse, der måles kolorimetrisk ved 550 nm.
Aldehydes derived from furan, the main one being hydroxymethylfurfural, react with barbituric acid and paratoluidine to give a red compound which is determined by colorimetry at 550 nm.
Højtryksvæskekromatografi (HPLC)
High-performance liquid chromatography (HPLC)
Adskillelse ved omvendt fase-søjlekromatografi og bestemmelse ved 280 nm.
Separation through a column by reversed-phase chromatography and determination at 280 nm.
Spektrofotometer til måling mellem 300 og 700 nm.
Spectrophotometer for making measurements between 300 and 700 nm.
Glaskuvetter med en optisk vejlængde på 1 cm.
Glass cells with optical paths of 1 cm.
0,5 % (m/v) barbitursyreopløsning
Barbituric acid, 0,5 % solution (m/v).
500 mg barbitursyre (C4O3N2H4) opløses i destilleret vand under svag opvarmning på vandbad ved 100 °C.
Dissolve 500 mg of barbituric acid, C4O3N2H4, in distilled water and heat slightly over a waterbath at 100 °C.
Der fyldes op til 100 ml med destilleret vand.
Make up to 100 ml with distilled water.
Opløsningen har en holdbarhed på ca. en uge.
The solution keeps for about a week.
10 % (m/v) paratoluidinopløsning
Paratoluidine solution, 10 % (m/v).
Opløsningen skal fornys dagligt.
This solution should be renewed daily.
Vandig ethanalopløsning (CH3CHO), 1 % (m/v)
Ethanal (acetaldehyde), CH3CHO, 1 % (m/v) aqueous solution.
Opløsningen fremstilles umiddelbart før brugen.
Prepare just before use.
Vandig opløsning af hydroxymethylfurfural (C6O3H6), 1 g/l
Hydroxymethylfurfural, C6O3H6, 1 g/l aqueous solution.
Ved successiv fortynding fremstilles opløsninger med et indhold på 5, 10, 20, 30 og 40 mg/l.
Prepare successive dilutions containing 5, 10, 20, 30 and 40 mg/l.
Opløsningen på 1 g/l og fortyndinger deraf skal fremstilles umiddelbart inden brugen.
The 1 g/l and the diluted solutions must be freshly prepared.
Bestemmelsen udføres på 2 ml af denne opløsning.
Carry out the determination on 2 ml of this solution.
Kolorimetriopløsning
Colorimetric determination
I to 25 ml kolber a og b med slibprop anbringes der 2 ml prøve fremstillet efter anvisningerne i 2.3.1.
Into each of two 25 ml flasks a and b fitted with ground glass stoppers place 2 ml of the sample prepared as in paragraph 2.3.1.
I hver kolbe tilsættes der 5 ml paratoluidinopløsning (2.2.2), hvorefter der blandes.
Place in each flask 5 ml of paratoluidine solution (paragraph 2.2.2); mix.
Til kolbe b (blind) sættes 1 ml destilleret vand og til kolbe a (prøve) 1 ml barbitursyreopløsning (2.2.1). Der blandes ved omrystning.
Add 1 ml of distilled water to flask b (control) and 1 ml barbituric acid solution (paragraph 2.2.1) to flask a. Shake to homogenize.
Kolbernes indhold overføres til spektrofotometrets kuvetter med 1 cm optisk vejlængde.
Transfer the contents of the flasks into spectrophotometer cells with optical paths of 1 cm.
Absorbansskalaen indstilles til nul med indholdet af kolbe b ved en bølgelængde på 550 nm, og absorbansvariationen for indholdet af kolbe a følges.
Zero the absorbence scale using the contents of flask b for a wavelength of 550 nm.
Den maksimale værdi A, som nås i løbet af 2-5 minutter, aflæses.
Follow the variation in the absorbence of the contents of flask a; record the maximum value A, which is reached after two to five minutes.
Prøver med et indhold af hydroxymethylfurfural over 30 mg/l skal fortyndes, inden de analyseres.
Samples with hydroxymethylfurfural concentrations above 30 mg/l must be diluted before the analysis.
Fremstilling af kalibreringskurve
Preparation of the calibration curve
I to sæt 25 ml kolber, a og b, anbringes der 2 ml af hver af opløsningerne af hydroxymethylfurfural på 5, 10, 20, 30 og 40 mg/l (2.2.4), hvorefter der gås frem som beskrevet under 2.3.2.
Place 2 ml of each of the hydroxymethylfurfural solutions with 5, 10, 20, 30 and 40 mg/l (paragraph 2.2.4) into two sets of 25 ml flasks a and b and treat them as described in paragraph 2.3.2.
Absorbanserne afbildes grafisk som funktion af koncentrationen af hydroxymethylfurfural. Kurven er en ret linje gennem nulpunktet.
The graph representing the variation of absorbence with the hydroxymethylfurfural concentration in mg/l is a straight line passing through the origin.
Indholdet af hydroxymethylfurfural i rektificeret koncentreret most udtrykkes i milligram pr. kg totalsukker.
The hydroxymethylfurfural concentration in rectified concentrated musts is expressed in milligrams per kilogram of total sugars.
Beregningsmåde
Method of calculation
Analyseprøvens indhold af hydroxymethylfurfural, C mg/l, aflæses ud for absorbansen A for denne prøve på kalibreringskurven.
The hydroxymethylfurfural concentration C mg/l in the sample to be analysed is that concentration on the calibration curve corresponding to the absorbence A measured on the sample.
Indhold af hydroxymethylfurfural i milligram pr. kg totalsukker:
The hydroxymethylfurfural concentration in milligrams per kilogram of total sugars is given by:
P = det procentvise totalindhold (m/m) af sukker i den rektificerede koncentrerede most.
P = percentage (m/m) concentration of total sugars in the rectified concentrated must.
Højtryksvæskekromatografi (HPLC)
High-performance liquid chromatography
HPLC-kromatograf forsynet med:
High-performance liquid chromatograph equipped with:
»loop«-injektor, 5 eller 10 µl
a loop injector, 5 or 10 μl,
spektrofotometerdetektor til måling ved 280 nm
spectrophotometer detector for making measurements at 280 nm,
octadecyleret silicagelsøjle (f.eks. Bondapak C18 — Corasil, Waters Ass.)
column of octadecyl-bonded silica (e.g.: Bondapak C18 — Corasil, Waters Ass.),
skriver, eventuelt med integrator
a recorder and, if required, an integrator,
Den mobile fases flow: 1,5 ml/min.
Flow rate of mobile phase: 1,5 ml/minute.
Membranfilter (0,45 µm)
Membrane filtration apparatus, pore diameter 0,45 µm.
Dobbeltdestilleret vand
Doubly distilled water.
Methanol (CH3OH), destilleret eller af HPLC-kvalitet
Methanol, CH3OH, distilled or HPLC quality.
Eddikesyre (CH3COOH) (ρ20 = 1,05 g/ml)
Acetic acid, CH3COOH, (ρ20 = 1,05 g/ml).
Mobil fase: vand, methanol (3.2.2) og eddikesyre (3.2.3), som forinden er membranfiltreret (0,45 μm), i forholdet 40:9:1 (v/v)
Mobile phase: water-methanol (paragraph 3.2.2)-acetic acid (paragraph 3.2.3) previously filtered through a membrane filter (0,45 µm), (40:9:1 v/v).
Denne mobile fase skal fremstilles hver dag og befries for luft inden anvendelsen.
This mobile phase must be prepared daily and outgassed before use.
Referenceopløsning af hydroxymethylfurfural, 25 mg/l (m/v)
Reference solution of hydroxymethylfurfural, 25 mg/l (v/v).
I en 100 ml målekolbe anbringes 25 mg nøjagtigt afvejet hydroxymethylfurfural (C6H3O6), og der fyldes op med methanol (3.2.2).
Into a 100 ml volumetric flask, place 25 mg of hydroxymethylfurfural, C6H3O6, accurately weighed, and make up to the mark with methanol (paragraph 3.2.2).
Opløsningen fortyndes 1:10 med methanol (3.2.2) og filtreres på membranfilter (0,45 µm).
Dilute this solution 1/10e with methanol (paragraph 3.2.2) and filter through a membrane filter (0,45 µm).
Denne opløsning anbringes i køleskab i en tæt tillukket brun glasflaske. Den har en holdbarhed på 2-3 måneder.
If kept in a hermetically sealed brown glass bottle in a refrigerator, this solution will keep for two to three months.
Der anvendes en opløsning fremstillet ved fortynding af rektificeret koncentreret most til 40 % (m/v) på følgende måde: 200 g nøjagtigt afvejet rektificeret koncentreret most overføres til en 500 ml målekolbe, hvorefter der fyldes op til mærket med vand, blandes og filtreres på membranfilter (0,45 µm).
Use the solution obtained by diluting the rectified concentrated must to 40 % (m/v) (introduce 200 g of accurately weighed rectified concentrated must into a 500 ml volumetric flask. Make up to the mark with water and homogenise) and filter it through a membrane filter (0,45 µm).
I kromatografen indsprøjtes 5 (eller 10) µl af den i 3.3.1 klargjorte prøve og 5 (eller 10) µl af referenceopløsningen af hydroxymethylfurfural (3.2.5).
Inject 5 (or 10) µl of the sample prepared as described in paragraph 3.3.1. and 5 (or 10) µl of the reference hydroxymethylfurfural solution (paragraph 3.2.5) into the chromatograph.
Kromatogrammet optages.
Record the chromatogram.
Retentionstiden for hydroxymethylfurfural er ca. 6-7 min.
The retention time of hydroxymethylfurfural is approximately six to seven minutes.
Indholdet af hydroxymethylfurfural i 40 % (m/v) opløsningen af koncentreret rektificeret most betegnes C mg/l.
Let the hydroxymethylfurfural concentration in the 40 % (m/v) solution of the rectified concentrated must be C mg/l.
I. Hurtig metode til vurdering af tungmetaller
I. Rapid method for evaluation of heavy metals
Tungmetallerne påvises i passende fortyndet rektificeret koncentreret most ved den farvning, der sker ved dannelse af sulfider.
Heavy metals are revealed in the suitably diluted rectified concentrated must by the coloration produced by the formation of sulphides.
Der sammenlignes med en standardopløsning med et blyindhold, som svarer til det højest tilladte indhold.
They are assessed by comparison with a standard lead solution corresponding to the maximum admissible concentration.
Bestemmelse af blyindholdet ved atomabsorptionsspektrofotometri
Determination of lead content by atomic absorption spectrophotometry
Det chelat, som bly danner med ammoniumpyrrolidindithiocarbamat, ekstraheres med methylisobutylketon, og absorbansen ved 283,3 nm måles.
The chelate given by lead with ammonium pyrrolidinedithiocarbamate is extracted with methylisobutylketone and the absorbence measured at 283,3 nm.
Blyindholdet bestemmes ved at analysere prøver, hvortil der med referenceopløsninger er tilsat en kendt mængde bly.
The lead content is determined by using known additional amounts of lead in a set of reference solutions.
Hurtig metode til vurdering af tungmetaller
Rapid method for evaluation of heavy metals
Fortyndet saltsyre, 70 % (m/v)
Dilute hydrochloric acid, 70 % (m/v).
Der afvejes 70 g saltsyre (HCl) (ρ20 = 1,16-1,19 g/ml) og fyldes op med vand til 100 ml.
Take 70 g of hydrochloric acid, HCl (ρ20 = 1,16 to 1,19 g/ml), and make up to 100 ml with water.
Fortyndet saltsyre, 20 % (m/v)
Dilute hydrochloric acid, 20 % (m/v).
Der afvejes 20 g saltsyre (HCl) (ρ20 = 1,16-1,19 g/ml) og fyldes op med vand til 100 ml.
Take 20 g of hydrochloric acid, HCl (ρ20 = 1,16 to 1,19 g/ml), and make up to 100 ml with water.
Fortyndet ammoniak
Dilute ammonia.
Der afvejes 14 g ammoniak (NH3) (ρ20 = 0,931-0,934 g/ml) og fyldes op med vand til 100 ml.
Take 14 g of ammonia, NH3 (ρ20 = 0,931 to 0,934 g/ml) and make up to 100 ml with water.
Bufferopløsning med pH 3,5
pH 3,5 buffer solution.
25 g ammoniumacetat (CH3COONH4) opløses i 25 ml vand, og der tilsættes 38 ml fortyndet saltsyre (2.1.1).
Dissolve 25 g of ammonium acetate (CH3COONH4), in 25 ml of water and add 38 ml of dilute hydrochloric acid (paragraph 2.1.1).
Om nødvendigt justeres pH med fortyndet saltsyre (2.1.2) eller fortyndet ammoniak (2.1.3), og der fyldes op med vand til 100 ml.
Adjust the pH if necessary with the dilute hydrochloric acid (paragraph 2.1.2) or the dilute ammonia (paragraph 2.1.3) and make up to 100 ml with water.
Thioacetamidopløsning (C2H5NS), 4 % (m/v)
Thioacetamide solution, (C2H5NS), 4 % (m/v).
Glycerolopløsning (C3H8O3), 85 % (m/v)
Glycerol solution, (C3H8O3, 85 % (m/v)
(n D20 °C = 1,449-1,455)
°C = 1,449 to 1,455).
Thioacetamidreagens
Thioacetamide reagent.
Til 0,2 ml thioacetamidopløsning (2.1.5) tilsættes 1 ml af en blanding af 5 ml vand, 15 ml 1 M natriumhydroxidopløsning og 20 ml glycerol (2.1.6).
To 0,2 ml of thioacetamide solution (paragraph 2.1.5) add 1 ml of a mixture of 5 ml of water, 15 ml of 1 M sodium hydroxide solution and 20 ml of glycerol (paragraph 2.1.6).
Der opvarmes på vandbad ved 100 °C i 20 sekunder.
Heat over a waterbath at 100 °C for 20 seconds.
Blyopløsning, 0,002 g/l
Solution containing 0,002 g/l of lead.
Der fremstilles en blyopløsning med 1 g/l ved at opløse 0,400 g blynitrat (Pb(NO3)2) i vand og fylde op til 250 ml med vand.
Prepare a 1 g/l lead solution by dissolving 0,400 g of lead nitrate, Pb (NO3)2, in water and making up to 250 ml with water.
Umiddelbart før brugen fortyndes denne opløsning til 2 promille (v/v) med vand, så man får en opløsning med 0,002 g/l.
At the time of use, dilute this solution with water to two parts in 1000 (v/v) in order to obtain a 0,002 g/l solution.
En prøve på 10 g rektificeret koncentreret most opløses i 10 ml vand.
Dissolve a test sample of 10 g of the rectified concentrated must in 10 ml of water.
Der tilsættes 2 ml bufferopløsning med pH 3,5 (2.1.4) og blandes.
Add 2 ml of the pH 3,5 buffer solution (paragraph 2.1.4); mix.
Der fremstilles efter samme fremgangsmåde en referenceopløsning ved hjælp af 10 ml blyopløsning med 0,002 g/l (2.1.8).
Prepare the control under the same conditions by using 10 ml of the 0,002 g/l lead solution (paragraph 2.1.8).
Efter to minutter må en eventuel brunfarvning af prøven med rektificeret koncentreret most ikke være kraftigere end farvningen af referenceprøven.
After two minutes, any brown coloration of the rectified concentrated must solution should not be more intense than that of the control.
Under de foreskrevne betingelser svarer referenceprøven til et højest tilladt blyindhold udtrykt i bly på 2 mg pr. kg rektificeret koncentreret most.
Under the conditions of the above procedure, the control sample corresponds to a maximum admissible heavy metal concentration expressed as lead of 2 mg/kg of rectified concentrated must.
Atomabsorptionsspektrofotometer med luft-acetylenbrænder.
Atomic absorption spectrophotometer equipped with an air-acetylene burner.
Blyhulkatodelampe
Lead hollow cathode lamp.
Fortyndet eddikesyre
Dilute acetic acid.
Der afvejes 12 g iseddike (ρ20 = 1,05 g/l) og fyldes op med vand til 100 ml.
Take 12 g of glacial acetic acid (ρ20 = 1,05 g/ml) and make up to 100 ml with water.
Opløsning af ammoniumpyrrolidindithiocarbamat (C5H12N2S2), 1 % (m/v)
Solution of ammonium pyrrolidinedithiocarbamate, C5H12N2S2, 1 % (m/v).
Methylisobutylketon (CH3)2 CHCH2COCH3
Methylisobutylketone, (CH3)2 CHCH2COCH3.
Blyopløsning, 0,010 g bly pr. l
Solution containing 0,010 g/l of lead.
Blyopløsningen med 1 g/l (2.1.8) fortyndes til 1 % (v/v).
Dilute the 1 g/l lead solution (paragraph 2.1.8) to 1 % (v/v).
Analyseopløsning
Preparation of solution to be examined
10 g rektificeret koncentreret most opløses i en blanding af lige store rumfang fortyndet eddikesyre (3.2.1) og vand, og der fyldes op til 100 ml med denne blanding.
Dissolve 10 g of rectified concentrated must in a mixture of equal volumes of dilute acetic acid (paragraph 3.2.1) and water, and make up to 100 ml with this mixture.
Der tilsættes 2 ml ammoniumpyrrolidindithiocarbamat (3.2.2) og 10 ml methylisobutylketon (3.2.3).
Add 2 ml of ammonium pyrrolidinedithiocarbamate solution (paragraph 3.2.2) and 10 ml of methylisobutylketone (paragraph 3.2.3).
Der omrystes i 30 sekunder afskærmet mod kraftig belysning.
Shake for 30 seconds while protected from bright light.
Opløsningen henstår, til de to lag skiller.
Leave the two layers to separate.
Laget af methylisobutylketon anvendes.
Use the methylisobutylketone layer.
Referenceopløsninger
Preparation of reference solutions
Der fremstilles tre referenceopløsninger, der ud over 10 g rektificeret koncentreret most indeholder henholdsvis 1, 2 og 3 ml af blyopløsningen med 0,010 g/l (3.2.4).
Prepare three reference solutions containing, in addition to 10 g of rectified concentrated must, 1, 2 and 3 ml respectively of the solution containing 0,010 g/l of lead (paragraph 3.2.4).
De behandles på samme måde som analyseopløsningen.
Treat these in the same way as the solution to be examined.
Der fremstilles en blindprøve på samme måde som anført i 3.3.1 for analyseopløsningen, men uden tilsætning af rektificeret koncentreret most.
Prepare a control by proceeding under the same conditions as in paragraph 3.3.1, but without the addition of the rectified concentrated must.
Bølgelængden indstilles til 283,3 nm.
Set the wavelength to 283,3 nm.
Methylisobutylketonfraktionen fra blindprøven forstøves i flammen, og absorbansen indstilles til nul.
Atomise the methylisobutylketone from the control sample in the flame and zero the absorbence scale.
Absorbansen bestemmes for ekstrakterne fra henholdsvis analyseopløsningen og referenceopløsningerne.
By operating with their respective solvent extracts, determine the absorbences of the solution to be examined and the reference solutions.
Blyindholdet udtrykkes i milligram pr. kilogram rektificeret koncentreret most med én decimal.
Express the lead content in milligrams per kilogram of rectified concentrated must to one decimal place.
Absorbanserne afbildes grafisk som funktion af koncentrationen af bly, der er tilsat til referenceopløsningerne, idet koncentrationen nul svarer til analyseopløsningen.
Plot the curve giving the variation in absorbence as a function of the lead concentration added to the reference solutions, zero concentration corresponding to the solution to be examined.
Den rette linje gennem punkterne forlænges, til den skærer koncentrationsaksen på den negative side.
Extrapolate the straight line joining the points until it cuts the negative part of the concentration axis.
Afstanden fra dette punkt til nulpunktet er blykoncentrationen i analyseopløsningen.
The distance of the point of intersection from the origin gives the lead concentration in the solution to be examined.
Kemisk måling af ethanol
Chemical determination of ethanol
Denne målemetode anvendes til bestemmelse af alkoholindholdet i væsker med lavt alkoholindhold, såsom most, koncentreret most og rektificeret koncentreret most.
This method is used for the determination of the alcoholic strength of low-alcohol liquids such as musts, concentrated musts and rectified concentrated musts.
Simpel destillation af væsken.
Simple distillation of the liquid.
Oxidation af ethanol i destillatet med kaliumdichromat.
Oxidation of the ethanol in the distillate by potassium dichromate.
Titrering af dichromatoverskuddet med en jern(II)-opløsning.
Titration of the excess dichromate with an iron (II) solution.
Destillationsapparat som det, der anvendes til måling af alkoholindhold.
Distillation apparatus used to measure the alcoholic strength
Kaliumdichromatopløsning
Potassium dichromate solution.
33,600 g kaliumdichromat (K2Cr2O7) opløses i en mængde vand, som er tilstrækkelig til at give 1 l ved 20 °C.
Dissolve 33,600 g of potassium dichromate, (K2Cr2O7), in sufficient quantity of water to make one litre of solution at 20 °C.
En milliliter af denne opløsning oxiderer 7,8924 mg alkohol.
One millilitre of this solution oxidizes 7,8924 mg of alcohol.
Opløsning af jern(II)ammoniumsulfat
Iron (II) ammonium sulphate solution.
135 g jern(II)ammoniumsulfat (FeSO4(NH4)2SO4, 6 H2O) opløses i en mængde vand, som er tilstrækkelig til at give 1 l, og der tilsættes 20 ml koncentreret svovlsyre (H2SO4) (ρ20 = 1,84 g/ml).
Dissolve 135 g of iron (II) ammonium sulphate, Fe SO4, (NH4)2SO4, 6 H2O in sufficient quantity of water to make one litre of solution and add 20 ml of concentrated sulphuric acid, (H2SO4), (ρ20 = 1,84 g/ml).
Kaliumpermanganatopløsning
Potassium permanganate solution.
1,088 g kaliumpermanganat (KMnO4) opløses i en mængde vand, som er tilstrækkelig til at give 1 l.
Dissolve 1,088 g of potassium permanganate, KMnO4, in a sufficient quantity of water to make one litre of solution.
Fortyndet svovlsyre 1:2 (v/v)
Sulphuric acid, diluted 1:2 (v/v).
Til 500 ml vand tilsættes gradvist og under omrøring 500 ml svovlsyre (H2SO4) (ρ20 = 1,84 g/ml).
A little at a time and stirring continuously, add 500 ml of sulphuric acid, (H2SO4) (ρ20 = 1,84 g/ml) to 500 ml of water.
Ferro-orthophenanthrolin-reagens
Ferrous orthophenanthroline reagent.
0,695 g jern(II)sulfat (FeSO4, 7 H2O) opløses i 100 ml vand, og der tilsættes 1,485 g orthophenanthrolinmonohydrat (C12H8N2, H2O).
Dissolve 0,695 g of ferrous sulphate, FeSO4, 7 H2O, in 100 ml of water, and add 1,485 g of orthophenanthroline monohydrate, C12H8N2, H2O.
Opløsningen fremskyndes ved opvarmning.
Heat to help the dissolution.
Opløsningen, som har en kraftig rød farve, har god holdbarhed.
This bright red solution keeps well.
100 g rektificeret koncentreret most og 100 ml vand anbringes i destillationskolben.
Place 100 g of rectified concentrated must and 100 ml of water in the distillation flask.
Destillatet opsamles i en 100 ml målekolbe, og der fyldes op til mærket med vand.
Collect the distillate in a 100 ml volumetric flask and make up to the mark with water.
I en 300 ml kolbe med slibprop og tragtformet hals, så halsen kan skylles uden tab, anbringes 20 ml af den indstillede kaliumdichromatopløsning (3.1) og 20 ml fortyndet svovlsyre 1:2 (v/v) (3.4), og der omrystes.
Take a 300 ml flask with a ground glass stopper and with a widened neck enabling the neck to be rinsed without loss. In the flask, place 20 ml of the titrant potassium dichromate solution (paragraph 3.1) and 20 ml of the 1:2 (v/v) dilute sulphuric acid (paragraph 3.4) and shake.
Der tilsættes 20 ml destillat.
Add 20 ml of the distillate.
Kolben tilproppes, og efter omrystning henstår blandingen i mindst 30 minutter under jævnlig omrystning (måleprøve).
Stopper the flask, shake, and wait at least 30 minutes, shaking occasionally. (This is the ‘measurement’ flask.)
Opløsningen af jern(II)ammoniumsulfat (3.2) indstilles i forhold til kaliumdichromatopløsningen, idet der i en tilsvarende kolbe hældes samme mængder reagenser, mens de 20 ml destillat erstattes af 20 ml destilleret vand (blindprøve).
Carry out the titration of the iron (II) ammonium sulphate solution (paragraph 3.2) with respect to the potassium dichromate solution by placing in an identical flask the same quantities of reagents but replacing the 20 ml of distillate by 20 ml of distilled water. (This is the ‘control’ flask.)
Til kolben med måleprøven sættes fire dråber orthophenanthrolin-reagens (3.5).
Add four drops of the orthophenanthroline reagent (paragraph 3.5) to the contents of the ‘measurement’ flask.
Overskuddet af dichromat titreres med opløsningen af jern(II)ammoniumsulfat (3.2).
Titrate the excess dichromate by adding to it the iron (II) ammonium sulphate solution (paragraph 3.2).
Tilsætningen af jern(II)-opløsningen standses, når blandingen skifter fra blågrøn til mørkebrun.
Stop adding the ferrous solution when the mixture changes from green-blue to brown.
For at bestemme omslaget nøjagtigt titreres der tilbage fra mørkebrun til blågrøn med kaliumpermanganatopløsningen (3.3).
To judge the end-point more precisely, change the colour of the mixture back from brown to green-blue with the potassium permanganate solution (paragraph 3.3).
En tiendedel af det rumfang af opløsningen, der er anvendt, trækkes fra det forbrugte rumfang af jern(II)ammoniumsulfatopløsningen.
Subtract a tenth of the volume of this solution used from the volume of the iron (II) solution added.
Forskellen betegnes n.
Let the difference be n ml.
Ethanolindholdet udtrykkes i gram pr. kg totalsukker med én decimal.
The ethanol is expressed in grams per kilogram of total sugars and is quoted to one decimal place.
n′ ml jern(II)-opløsning reducerer 20 ml dichromatopløsning, som oxiderer 157,85 mg ren ethanol.
n′ ml of ferrous solution reduces 20 ml of dichromate solution which oxidizes 157,85 mg of pure ethanol.
En milliliter af jern(II)-opløsningen har samme reducerende virkning som
One millilitre of iron (II) solution has the same reducing power as:
((157,85)/(n′)) mg ethanol
((157,85)/(n)) mg of ethanol
n′ – n ml af jern(II)-opløsningen har samme reducerende virkning som
n-n′ ml of iron (II) solution have the same reducing power as: