AcidBaseTitrations;63:ConceptsinAcidBaseTitrations;Titrations provide a method of quantitatively measuring the concentration of an unknown solution. In an;acid-base titration, this is done by delivering a titrant of known concentration into an analyte of known;volume. (The concentration of an unknown titrant can also be determined by titration with an analyte of;known concentration and volume.) Titration curves (graphs of volume vs. pH) have characteristic shapes.;The graph can be used to determine the strength or weakness of an acid or base. The equivalence point of;the titration, or the point where the analyte has been completely consumed by the titrant, is identified by;the point where the pH changes rapidly over a small volume of titrant delivered. There is a steep incline;or decline at this point of the titration curve. It is also common to use an indicator that changes color at or;near the equivalence point. In this assignment, you will observe this titration curve by titrating the strong;acid HCl with the strong base NaOH.;1.;Start Virtual ChemLab, select Acid-Base Chemistry, and then select Concepts in Acid-Base;Titrations from the list of assignments. The lab will open in the Titration laboratory.;2.;Click the Lab Book to open it. The buret will be filled with NaOH. The horizontal position of the;orange handle is off for the stopcock. Click the Save button in the Buret Zoom View window.;Open the stopcock by pulling down on the orange handle. The vertical position delivers solution;the fastest with three intermediate rates in between. Turn the stopcock to one of the fastest;positions. Observe the titration curve. When the volume reaches 35 mL, double-click the;stopcock to stop the titration. Click Stop in the Buret Zoom View. A blue data link will be;created in the lab book, click on it to view the data.;3.;The beaker contains 0.3000 M HCl and the buret contains 0.3000 M NaOH.;4.;Write a complete balanced equation for the neutralization reaction between HCl and NaOH.;The following questions can be answered by examining the Plot and Data Viewer windows.;5.;What was the pH and color of the solution at the beginning of the titration?;6.;What was the pH and color of the solution at the end of the titration?;133;Virtual ChemLab: General Chemistry, Student Lab Manual/Workbook, V. 4.5, by Brian F. Woodfield, Matthew C. Asplund, and Steven Haderlie. Published by;Prentice Hall. Copyright 2013 by Pearson Education, Inc.;Acid-Base Chemistry;7.;Examine the graph of the pH vs. volume (blue line).;Sketch the shape of the titration graph of pH vs. volume.;8.;What happens to the pH around 25 mL?;9.;What would cause the change observed in question #4?;134;Virtual ChemLab: General Chemistry, Student Lab Manual/Workbook, V. 4.5, by Brian F. Woodfield, Matthew C. Asplund, and Steven Haderlie. Published by;Prentice Hall. Copyright 2013 by Pearson Education, Inc.
Paper#16503 | Written in 18-Jul-2015Price : $47