Please be specific!
Briefly explain whether each if the following procedural errors would result in a high, low, or an unchanged calculated mass of Ca2+ in the analyzed tablet.
a)a student had difficulty decanting the supernatant solution from the test tubes in step 9, causing him to transfer some of the solid along with the solution.
b)when rinsing the binder material from the test tubes, student observed small pieces of undissolved tablet in the solid at the bottom of the tubes.
c)a student found that the litmus paper did not turn blue when tested with a drop of the solution, then failed to add additional Na_2_CO_3_ solution and test the solution again beforeproceeding to the next step.
d)a student discarded the torn-off filter paper corner, instead of placing it in the cone
e)after labeling the filter paper, a student left wet fingerprints on the paper when transferring it to the balance to determine its mass.
f)a student failed to determine the mass of the filter paper prior to filtering the CaCO_3_. Realizing the importance of this mass, he selected a new piece of filter paper and used its mas in his calculations.
2)Briefly expalin why you can use this experiment's procedure to determine the number of milligrams of Ca2+ ion in a food sample in which the Ca2+ ion is present in a form ofther than CaCO_3_
See your post under the screen name anne.
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a) If the student transferred some of the solid along with the solution, the calculated mass of Ca2+ in the analyzed tablet would be high. This is because the solid that was transferred contains Ca2+ ions, which would contribute to an overestimation of the mass of Ca2+ in the tablet.
b) If there were small pieces of undissolved tablet in the solid at the bottom of the tubes, the calculated mass of Ca2+ in the analyzed tablet would be low. This is because some of the Ca2+ ions may have remained in the undissolved pieces of the tablet and were not included in the analysis.
c) If the litmus paper did not turn blue when tested with a drop of the solution and the student did not add additional Na2CO3 solution and retest, the calculated mass of Ca2+ in the analyzed tablet would be unchanged. This is because the failure to test the solution again would not affect the measurement of Ca2+ ions in the tablet.
d) If the student discarded the torn-off filter paper corner instead of placing it in the cone, the calculated mass of Ca2+ in the analyzed tablet would be unchanged. This is because the torn-off filter paper corner does not have any effect on the measurement of Ca2+ ions in the tablet.
e) If the student left wet fingerprints on the filter paper when transferring it to the balance, the calculated mass of Ca2+ in the analyzed tablet would be high. This is because the wet fingerprints would add extra mass to the filter paper, leading to an overestimation of the mass of Ca2+ in the tablet.
f) If the student failed to determine the mass of the filter paper prior to filtering the CaCO3 and used a new piece of filter paper for calculations, the calculated mass of Ca2+ in the analyzed tablet would be high. This is because the unused new filter paper would have a different mass than the one used for filtering, leading to an overestimation of the mass of Ca2+ in the tablet.
2) This experiment's procedure can be used to determine the number of milligrams of Ca2+ ion in a food sample even when the Ca2+ ion is present in a form other than CaCO3 because the procedure involves converting all the calcium compounds present in the food sample to CaCO3. Since the analysis is based on the measurement of CaCO3, regardless of the form in which the calcium is initially present, the procedure allows for the accurate determination of the number of milligrams of Ca2+ ion.
a) The error of transferring solid along with the solution would result in a high calculated mass of Ca2+ in the analyzed tablet. This is because some of the solid, which contains Ca2+, would be mistakenly included in the solution that is supposed to be decanted. As a result, the mass of Ca2+ would be overestimated.
b) The observation of small pieces of undissolved tablet in the solid at the bottom of the tubes would result in an unchanged calculated mass of Ca2+ in the analyzed tablet. This is because the undissolved tablet does not contribute to the mass of Ca2+ being analyzed.
c) The failure to add additional Na_2_CO_3_ solution and retest the solution, despite the litmus paper not turning blue, would result in a low calculated mass of Ca2+ in the analyzed tablet. This is because the blue color of the litmus paper indicates the presence of CO3^2- ion, which reacts with Ca2+ to form CaCO3. By not adding additional Na_2_CO_3_ solution and retesting, the reaction may not proceed fully, resulting in an incomplete precipitation of CaCO3 and lower measured mass.
d) Discarding the torn-off filter paper corner instead of placing it in the cone would result in an unchanged calculated mass of Ca2+ in the analyzed tablet. This is because the torn-off corner does not contribute to the measurement of Ca2+.
e) Leaving wet fingerprints on the filter paper when transferring it to the balance would result in a high calculated mass of Ca2+ in the analyzed tablet. This is because the wet fingerprints would add extra mass to the filter paper, leading to an overestimation of the measured mass of Ca2+.
f) Failing to determine the mass of the filter paper prior to filtering the CaCO3 and selecting a new piece of filter paper would result in an unchanged calculated mass of Ca2+ in the analyzed tablet. This is because the mass of the filter paper is subtracted from the total mass of the filtered CaCO3 to determine the mass of Ca2+. Choosing a new piece of filter paper would not affect this calculation since the mass of the chosen filter paper is still subtracted from the total mass.
2) This experiment's procedure can be used to determine the number of milligrams of Ca2+ ion in a food sample, even if the Ca2+ ion is present in a form other than CaCO3. This is because the procedure involves the precipitation of Ca2+ ions as CaCO3 through a reaction with sodium carbonate (Na2CO3) solution. As long as the Ca2+ ions can react with the Na2CO3 to form CaCO3, the experiment can measure the mass of the resulting precipitate and calculate the amount of Ca2+ ion present.