Nitrite concentration is commonly determined by interpolation method using spectrophotometry (an instrumental method) by a reaction called Griess Reaction. In this reaction, the sample containing nitrite is reacted with sulfanilamide and N-(1- Napthyl) ethylenediamine to form a colored species that absorbs at 550 nm. Using automated flow analysis instrument, the following results were obtained for the standard solutions of nitrite and for a sample containing an unknown amount. Concentration of Standard Solutions (x-axis) 2.000 UM 6.000 UM 10.00 UM 14.00 UM 18.00 UM Unknown Instrument Response (y-axis) 0.065 0.205 0.338 0.474 0.598 0.186 The instrument response (y-axis, absorbance at 550 nm) is plotted against standard concentration (x-axis, concentration) to obtain the calibration curve. Access the calibration curve using this link (open in a new window). Linear regression analysis was used to obtain the regression equation (y = mx + b) and found out to be y = 0.03338 x + 0.00225. Calculate the concentration of nitrite the unknown sample using the regression equation. Express your answers in 4 significant figures.

Nitrite concentration is commonly determined by interpolation method using spectrophotometry (an instrumental method) by a reaction called Griess Reaction. In this reaction, the sample containing nitrite is reacted with sulfanilamide and N-(1- Napthyl) ethylenediamine to form a colored species that absorbs at 550 nm. Using automated flow analysis instrument, the following results were obtained for the standard solutions of nitrite and for a sample containing an unknown amount. Concentration of Standard Solutions (x-axis) 2.000 UM 6.000 UM 10.00 UM 14.00 UM 18.00 UM Unknown Instrument Response (y-axis) 0.065 0.205 0.338 0.474 0.598 0.186 The instrument response (y-axis, absorbance at 550 nm) is plotted against standard concentration (x-axis, concentration) to obtain the calibration curve. Access the calibration curve using this link (open in a new window). Linear regression analysis was used to obtain the regression equation (y = mx + b) and found out to be y = 0.03338 x + 0.00225. Calculate the concentration of nitrite the unknown sample using the regression equation. Express your answers in 4 significant figures.

Appl Of Ms Excel In Analytical Chemistry

2nd Edition

ISBN:9781285686691

Author:Crouch

Publisher:Crouch

Chapter12: Spectrochemical Methods

Section: Chapter Questions

Problem 7P

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