The following data are the results of an experiment in which 0.5mL aliquots of invertase solutions in 0.1M acetate buffer pH 4.7 were equilibrated at different temperatures for 5 min. 0.5mL of sucrose in 0.1M acetate buffer pH 4.7 was then added and the tubes were incubated for a further 6 min exactly. 1mL of DNS in NaOH was then added, the tubes were removed from the waterbath and all of the tubes were boiled for 5min. After cooling and addition of 5 mL H₂O the absorbance was measured at 540nm. Temperature (°C) Absorbance at 540nm 0 19 30 40 50 70 100 0.144 0.362 0.600 0.900 1.142 0.301 0.426 Use this information to say which of the following answers is TRUE O Invertase retains some activity at 100°c All of the statements are true Invertase denatures at 50°c The exact temperature optimum of invertase cannot be determined from this experiment. O Invertase is less active at 19°c than 100°c

The following data are the results of an experiment in which 0.5mL aliquots of invertase solutions in 0.1M acetate buffer pH 4.7 were equilibrated at different temperatures for 5 min. 0.5mL of sucrose in 0.1M acetate buffer pH 4.7 was then added and the tubes were incubated for a further 6 min exactly. 1mL of DNS in NaOH was then added, the tubes were removed from the waterbath and all of the tubes were boiled for 5min. After cooling and addition of 5 mL H₂O the absorbance was measured at 540nm. Temperature (°C) Absorbance at 540nm 0 19 30 40 50 70 100 0.144 0.362 0.600 0.900 1.142 0.301 0.426 Use this information to say which of the following answers is TRUE O Invertase retains some activity at 100°c All of the statements are true Invertase denatures at 50°c The exact temperature optimum of invertase cannot be determined from this experiment. O Invertase is less active at 19°c than 100°c

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter13: Titrations In Analytical Chemistry

Section: Chapter Questions

Problem 13.5QAP

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