A technician you supervise is to determine the moisture content of a food product by the...
A technician you supervise is to determine the moisture content of a food product by the Karl Fischer method. Your technician wants to know what is this "Karl Fischer Reagent Water Equivalence" that is used in the equation to calculate percentage of moisture in the sample, why is it necessary, and how it is determined. Give the technician your answer.
Homework Answers
Karl Fischer reagent incorporates iodine, sulphur dioxide, pyridine and methanol. It is used in the determination of water content and moisture of drug substances. Karl Fischer method requires very less sample and is very quick and specific. Sometimes equal volumes of mixed methanol and formamide is used in the determination of moisture content. The water equivalent of the KFR is about 5mg water per mL of the reagent. Iodine is added by burette during titration. Water is a major component. The solvent generally methanol is involved in the reaction. A base keeps the pH 5-7.
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A technician you supervise is to determine the moisture content
of a food product by the...
A laboratory technician wants to determine the aspirin content of a headache pill by acid-base titration....
A laboratory technician wants to determine the aspirin content of a headache pill by acid-base titration. Aspirin has a Ka of 3.0 x 10−4. If the pill is dissolved in water to give a solution about 0.0050 M, what is the pH of this solution? (Neglect dilution effects.) If the solution in the problem above is then titrated against KOH solution, what will be the pH at the stoichiometric point.
A laboratory technician wants to determine the aspirin content of a headache pill by acid-base titration....
A laboratory technician wants to determine the aspirin content of a headache pill by acid-base titration. Aspirin has a Ka of 3.0 x 10−4. If the pill is dissolved in water to give a solution about 0.0050 M, what is the pH of this solution? (Neglect dilution effects.) 2.97 If the solution in the problem above is then titrated against KOH solution, what will be the pH at the stoichiometric point .
B. The moist weight of 0.028 m3 of a soil is 52 kg. The moisture content...
B. The moist weight of 0.028 m3 of a soil is 52 kg. The moisture content and the specific gravity of the soil solids are determined in the laboratory to be 11% and 2.7 , respectively. Calculate the following: Moist unit weight (kg/m3) i. Dry unit weight (kg/m3) ii. Void ratio d. Porosity iii. iv. Degree of saturation (%) Volume occupied by water (m3) v. ngle C. For the soil sample in A (above) represent the following on a soil...
5. A sample of aggregate has a moisture content of 10 percent. Its absorption capacity is...
5. A sample of aggregate has a moisture content of 10 percent. Its absorption capacity is 4 percent. What is the weight of free water in a 100-1b sample of this aggregate? How is fineness modulus measured and what does it represent The specific gravity and bulk density of an aggregate are 2.6 and 95 pcf respectively. Find the loose (bulk) volume of a 190-lb sample. A sample of fine aggregate with a specific gravity of 2.6 has a bulk...
Question Round your answer to the nearest integer The energy content of a certain food is...
Question Round your answer to the nearest integer The energy content of a certain food is to be determined in a bomb calorimeter that contains 2 kg of water by burning a 5-g sample of it in the presence of 136 g of air in the reaction chamber. If the water temperature rises by 3.2°C when equilibrium is established, determine the energy content of the food, in kJ/kg, by neglecting the thermal energy stored in the reaction chamber and the...
You use Kjeldahl method to determine protein content of a food: – You took 0.5 g...
You use Kjeldahl method to determine protein content of a food: – You took 0.5 g food – You used 12.6 mL HCl of 0.1010 N to titrate the NH3 that is trapped in boric acid – Determine in sequence: 1) mmole of NH3; 2) gram of N; 3) gram of protein (use 6.25 factor); 4) protein content of this food, in %
1. You are a food scientist trying to determine the nutritional content of certain food samples....
1. You are a food scientist trying to determine the nutritional content of certain food samples. Foor food sample D you preform a Benedict test to see if it contains any monosaccharides. For this test, you take 3 droplets of food sample D and mix it with 2 droplets of the Benedict test solution. The solution is heated for 5 minutes and you observe the color of the solution changing from blue to green to orange. A color change from...
The Kjeldahl method is the most widely used method for determining the protein content of foods....
The Kjeldahl method is the most widely used method for determining the protein content of foods. It is based on the fact that protein is the only macronutrient (major nutrient) that contains nitrogen. The method gives the value of g of nitrogen per 100 g of food. That value is then multiplied by a constant, 6.25 g protein per g of nitrogen, to give the result expressed as g of protein per 100 g of food. a. Explain why this...
You want to determine the protein content in milk with the Kjeldahl method. You take 100...
You want to determine the protein content in milk with the Kjeldahl method. You take 100 g whole milk and use 100 mL of 0.5 M hydrochloric acid to collect ammonia. You needed 34.50 mL of 0.3512 M NaOH for the back-titration. Calculate the percentage of protein in the sample where CP = 6.38 (that is % protein = CP x %N) **PLEASE SHOW ME STEP BY STEP CALCULATION**
just the last one Energy Content of Foods DATA Sample 2 Popcorn Sample 1 Rip 1...
just the last one
Energy Content of Foods DATA Sample 2 Popcorn Sample 1 Rip 1 218 Food used Mass of food and holder (initial) Mass of food and holder (final) Mass of empty can Mass of can plus water Initial water temperature Final water temperature 978 1018 63.44 18.5 °C 22.4°C JEN 2,7 °c 36.5 °C PROCESSING THE DATA 1. Calculate change in water temperature, Ar, for each sample, by subtracting the initial temperature from the final temperature (Ar=tfinal-initial)...
B. The moist weight of 0.028 m3 of a soil is 52 kg. The moisture content and the specific gravity of the soil solids are determined in the laboratory to be 11% and 2.7 , respectively. Calculate the following: Moist unit weight (kg/m3) i. Dry unit weight (kg/m3) ii. Void ratio d. Porosity iii. iv. Degree of saturation (%) Volume occupied by water (m3) v. ngle C. For the soil sample in A (above) represent the following on a soil...
5. A sample of aggregate has a moisture content of 10 percent. Its absorption capacity is 4 percent. What is the weight of free water in a 100-1b sample of this aggregate? How is fineness modulus measured and what does it represent The specific gravity and bulk density of an aggregate are 2.6 and 95 pcf respectively. Find the loose (bulk) volume of a 190-lb sample. A sample of fine aggregate with a specific gravity of 2.6 has a bulk...
Question Round your answer to the nearest integer The energy content of a certain food is to be determined in a bomb calorimeter that contains 2 kg of water by burning a 5-g sample of it in the presence of 136 g of air in the reaction chamber. If the water temperature rises by 3.2°C when equilibrium is established, determine the energy content of the food, in kJ/kg, by neglecting the thermal energy stored in the reaction chamber and the...
The Kjeldahl method is the most widely used method for determining the protein content of foods. It is based on the fact that protein is the only macronutrient (major nutrient) that contains nitrogen. The method gives the value of g of nitrogen per 100 g of food. That value is then multiplied by a constant, 6.25 g protein per g of nitrogen, to give the result expressed as g of protein per 100 g of food. a. Explain why this...
just the last one
Energy Content of Foods DATA Sample 2 Popcorn Sample 1 Rip 1 218 Food used Mass of food and holder (initial) Mass of food and holder (final) Mass of empty can Mass of can plus water Initial water temperature Final water temperature 978 1018 63.44 18.5 °C 22.4°C JEN 2,7 °c 36.5 °C PROCESSING THE DATA 1. Calculate change in water temperature, Ar, for each sample, by subtracting the initial temperature from the final temperature (Ar=tfinal-initial)...
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