# How do you calculate dissolved oxygen using Winkler method?

## How do you calculate dissolved oxygen using Winkler method?

The Winkler Method – Measuring Dissolved Oxygen

1. The Winkler method is done by noting a color change when titrating a fresh water sample.
2. The Winkler method for measuring dissolved oxygen involves titrating a sample with a series of reagents.
3. Oxygen solubility at different water temperatures.

## How do you calculate dissolved oxygen?

Dissolved oxygen levels can be measured by a basic chemical analysis method (titration method), an electrochemical analysis method (diaphragm electrode method), and a photochemical analysis method (fluorescence method). The diaphragm electrode method is the most widely used method.

What is the equivalent weight of oxygen in Winkler’s method?

So, the mass per mole of O2 is 32.00 g / mol, and the equivalent weight is 32.00 grams.

How is bod calculated?

Dissolved oxygen (D.O.) is measured by probe before and after incubation. BOD is computed based on the difference between initial and final D.O. The test uses dilution water and a known amount of sample in a 250-300 ml incubation bottle.

### How is do measured?

DO is measured using a dissolved oxygen meter (or DO meter). The best method is to take the measurement in the field at the same time each day, because DO concentrations can vary throughout a 24 hour period.

### Why MnSO4 is adding in Winkler’s method?

In the Winkler method,add MnSO4 and basic KI solution to the water sample. The product,Mn(OH)2 is oxided by the dissolved oxygen to Mn(OH)3, which reacts with KI when add H2SO4 to make the solution acid. The dissolved oxygen can be valued. In order to delete the interference of NO2-, add NaN3 in it.

What is Winkler A and B?

The Winkler test is used to determine the concentration of dissolved oxygen in water samples. In the test, an excess of manganese(II) salt, iodide (I−) and hydroxide (OH−) ions are added to a water sample causing a white precipitate of Mn(OH)2 to form.

How do you calculate oxygen concentration in water?

1 Determine water temperature in degrees C and find the value on the temperature scale. F to C conversion: [(F – 32) x 5] ÷ 9 2 Determine dissolved oxygen (DO) and find the value on the lower scale (Note: you result can be in mg/L or ppm). 3 Using a straight edge (ruler, piece of paper etc.)

## What is the titrant used in Winkler’s test?

How is BOD and COD calculated?

The COD test should be considered an independent measure of the organic matter in a wastewater sample rather than a substitute for the BOD test….Can I use my COD results to predict my BOD?

Sample 1: COD = 2,150 mg/L BOD = 1,100 mg/L
COD ÷ BOD = 2,150 ÷ 1,100 = 1.95
Sample 2: COD = 1,990 mg/L BOD = 1,050 mg/L

What are the applications of Winkler titration?

For these reasons, the Winkler titration is often employed for accurate determination of oxygen concentrations in aqueous samples. 2. -1. The method is suitable for the assay of oceanic levels of oxygen in uncontaminated seawater and is based on the Carpenter (1965) modification of the traditional Winkler titration.

### What is the Winkler method?

The Winkler Method is a technique used to measure dissolved oxygen in freshwater systems. Dissolved oxygen is used as an indicator of the health of a water body, where higher dissolved oxygen concentrations are correlated with high productivity and little pollution.

### What is the Winkler method for measuring dissolved oxygen?

The Winkler method is done by noting a color change when titrating a fresh water sample. Photo provided by Monica Bruckner. Microbial Life > Research Methods > Environmental Sampling > Dissolved Oxygen by the Winkler Method The Winkler Method – Measuring Dissolved Oxygen Created by Monica Z. Bruckner, Montana State University

How accurate is the Winkler test?

The Winkler test is often controversial as it is not 100% accurate and the oxygen levels may fluctuate from test to test despite using the same constant sample. In the first step, manganese (II) sulphate (at 48% of the total volume) is added to an environmental water sample.