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Unit 7: Acids, Bases, and Solutions Notebook Labs

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The following items should be in the Unit 7 portion of your notebook.  They should be clearly organized and easy to find.  Use an organizational system and label all work. Each lab will be graded separately.  All lab grades will be entered into the gradebook. 



Lab ABS1 -  Dissolving Rates

Question:
What is the effect of crystal size, degree of stirring and solvent temperature on the rate at which a solute dissolves in water?  How can these effects be explained.

Purpose:
To determine the effects of crystal size, degree of stirring and solvent temperature on the rate at which a solute dissolves in water and to explain the effects in terms of the surface model theory of dissolution.

Safety:
Copper (II) Sulfate is moderately toxic by ingestion and is a skin and respiratory irritant.  Avoid contact with skin and eyes. Wear chemical goggles at all times.

Disposal:
The copper solutions should be dumped into the large glass container;  they should not be poured down the drain.

A complete lab write-up includes a Title, a Purpose section, a Data section, a Conclusion and a Discussion of Results section.  The Data section should include a documented record of each test which was performed and the resulting observations and data.  The record should include a brief statement of the procedural step which was performed and the result of the procedure. The Conclusion should include one to three sentences which identifies the effect of the three variables upon the dissolving rate.  The Discussion of Results explains each of these effects individually in terms of the surface model theory of dissolution.






Lab ABS2 - Solubility Curves Lab

Question:
What does the solubility curve of potassium nitrate look like?

Purpose:
To collect experimental data in order to construct the solubility curve for potassium nitrate.

Safety:
Potassium nitrate in solid form is a strong oxidant and a fire and explosion risk when heated or in contact with organic material.  It is also a skin and eye irritant.  Wear safety goggles at all times.

Disposal:
Solutions can be poured down the drain and rinsed with water.  Clean all test tubes.  Wipe your station down before leaving the lab.

A complete lab write-up includes a Title, a Purpose section, a Data section, and a Conclusion/Discussion..  The Data section should include the provided data table;  it should be completed and taped in.  Calculations should be shown for indicated rows for the three trials which were personally conducted. A plot of solubility (y-axis) vs. temperature should be completed and taped in.  The Conclusion/Discussion should describe the plotted data and the dependence of solubility upon temperature.  The Conclusion/Discussion should also compare the experimental plot to the theoretical plot; similarities and differences should be noted.








Lab ABS3 - Acid-Base Neutralization

Question:
What is the relationship between the amount of acid and base involved in a neutralization reaction? How can the relationship be expressed as an equation written in terms of Macid, Vacid, Mbase, and Vbase? And what is the molarity of the unknown solutions Acid X and Base Y.

Purpose:
To discover the relationship between the amount of acid and base involved in a neutralization reaction, to express it as an equation written in terms of Macid, Vacid, Mbase, and Vbase, and to use the equation to determine the molarity of Acid X and Base Y solutions.

Safety:
All of the acids and bases used in this lab are corrosive to eyes, skin and other body tissues. They are toxic by ingestion. Clean up all spills immediately with plenty of cold water. Phenolpthalein is an alcohol-based solution; keep away from open flames. Wear chemical splash goggles at all times.

Disposal:
Test tubes should be rinsed and their contents poured down the drain. Bottles should be immediately capped when done using. Avoid contaminating dropper tips.

A complete lab write-up includes a Title, a Purpose section, a Data section, and a Conclusion/Discussion..  The Data section should include the provided data table;  it should be completed and taped in.  Calculations should be shown in an organized fashion for the unknown solutions X and Y. The Conclusion should include two sentences - one that states the relationship in terms of an equation and one that states the molarity of Acid X solution and Base Y solution:








Lab ABS4 - Acid-Base Properties

Question:
What are the properties of acids and bases?

Purpose:
To investigate and ultimately to describe how acids and bases behave in various situations.

Safety:
All of the acids and bases used in this lab are corrosive to eyes, skin and other body tissues. They are toxic by ingestion. Clean up all spills immediately with plenty of cold water. Magnesium metal is a flammable solid and burns with an intense flame. Phenolpthalein is an alcohol-bad solution, keep away from open flames. Wear chemical splash goggles at all times.

Disposal:
Solids should be placed in the garbage can.  Solutions can be poured down the drain and rinsed thoroughly with water.  Wipe down your lab station before leaving the lab.

A complete lab write-up includes a Title, a Purpose section, a Data section, and a Conclusion/Discussion section.  The Data section includes anorganized documentation of the various tests and the observed outcomes;  tests should be clearly described (including details);  observations should be clear and relevant.  The Conclusion/Discussion should identify each property of acids and bases which were discovered in this lab; references should be made to the observations in the Data section in support of the identified properties.








Lab ABS5 - Indicators

Question:
What is the approximate pH of a set of acid, base and salt solutions?

Purpose:
To use indicators to determine the approximate pH (the narrow range) of several acid, base, and salt solutions.

Safety:
Acids are corrosive to skin, clothing and eyes. Wear chemical splash goggles at all times and exercise care when handling acids - including the indicators.

Disposal:
All solutions can be poured down the drain and rinsed thoroughly with water. Please clean your lab bench, rinse your well plate and tidy up the indicator bottles before leaving lab.

A complete lab write-up includes a Title, a Purpose section, a Data section, a Conclusion section, and a Discussion of Results section.  The Data section should include an organized table for each tested solution; the indicator being used, the observed color and the resulting interpretation should be indicated.  Each data table should provide a trace of the logic used in your experimentation.  The Conclusion should use several short sentences to identify the approximate pH (the narrow range) of each solution. The Discussion of Results should include a mathematical analysis for each solution in which the pH is determined from the Ka (or Kb) value and concentration using an ICE table.  Once done, a statement should be made which evaluates the accuracy of the conclusion made for each solution.









Lab ABS6 - Titration Curve

Question:
How are the pH curves for a strong acid-strong base titration different than or similar to the pH curves for a weak acid-strong base titration?  How can the curves be interpretted?  How can the curves be used to determine the unkown molarity of acid?

Purpose:
To observe two types of acid-base titrations and to use the corresponding titration curves to determine the unknown molarity of the acid.

Safety:
Acids are corrosive to skin, clothing and eyes. Wear chemical splash goggles at all times and exercise care when handling acids.

Disposal:
All solutions can be poured down the drain and rinsed thoroughly with water. Burets should be emptied, cleaned and hung upside down in the buret holder. Please clean your lab bench, rinse your well plate and tidy up the indicator bottles before leaving lab.

A complete lab write-up includes a Title, a Purpose section, a Data section, a Conclusion section, and a Post-Lab Questions section.  The Data section should include the provided pH curves, cut out and taped in.  The curves should be marked on in response to the Post-Lab Questions.  The Conclusion should answer the question posed in the Purpose. The Post-Lab questions section should include a response to the provided Post-Lab Questions; discussion questions should be written in complete sentences (PUCS) and work should be clearly shown for the calculation questions (PSYW).

View Post-Lab Questions.









Lab ABS7 - Standardization of a Base

Question:
What is the molarity of a sodium hydroxide (NaOH) solution?

Purpose:
To determine the molarity of an aqueous solution of sodium hydroxide (NaOH) by titration with potassium terephthalate (KPH).

Safety:
Acids and bases are corrosive to skin, clothing and eyes. Wear chemical splash goggles at all times and exercise care when handling acids.

Disposal:
Unused or spilled pellets of sodium hydroxide should be placed in the garbage can. All solutions can be poured down the drain and rinsed thoroughly with water. Burets should be emptied, cleaned and hung upside down in the buret holder. Please clean your lab bench, rinse your well plate and tidy up the indicator bottles before leaving lab.

A complete lab write-up includes  a Title, a Purpose section, a Data section, and a Conclusion section. The Data section should include an organized table of  data for all titration trials (with units) and a collection of calculations for each trial.  Calculatons should be organized and follow-able;  short annotations must precede each calculation step. Attention should be given to significant digits and units. An average molarity value should be determined.  The Conclusion should use a single sentence to state the answer to the question posed in the Purpose









Lab ABS8 - Titration of Aspirin

Question:

What is the percent acid in asprin?

Purpose:
To determine the percent acid in asprin.

Safety:
Acids and bases are corrosive to skin, clothing and eyes. Wear chemical splash goggles at all times and exercise care when handling acids.

Disposal:
All solutions can be poured down the drain and rinsed thoroughly with water. Burets should be emptied, cleaned and hung upside down in the buret holder. Please clean your lab bench, rinse your well plate and tidy up the indicator bottles before leaving lab.


A complete lab write-up includes  a Title, a Purpose section, a Data section, a Conclusion section, and a Discussion of Results section. The Data section should include an organized table of  data for all titration trials (with units) and a collection of calculations for each trial.  Calculatons should be organized and follow-able;  short annotations must precede each calculation step. Attention should be given to significant digits and units. An average molarity value should be determined.  The Conclusion should use a single sentence to state the answer to the question posed in the Purpose. The Discussion of Results section should include a short paragraph in which you conduct an error analysis (discuss how well you did, identify any errors, and calculate a percent error). 










Lab ABS9 - Barney's Brew

Question:
What is the percent acid in vinegar?

Purpose:
To determine the percent acid in vinegar.

Safety:
Acids and bases are corrosive to skin, clothing and eyes. Wear chemical splash goggles at all times and exercise care when handling acids.

Disposal:
All solutions can be poured down the drain and rinsed thoroughly with water. Burets should be emptied, cleaned and hung upside down in the buret holder. Please clean your lab bench, rinse your well plate and tidy up the indicator bottles before leaving lab.

A complete lab write-up includes  a Title, a Purpose section, a Data section, and a Conclusion section. The Data section should include an organized table of  data for all titration trials (with units) and a collection of calculations for one trial.  An average molarity value should be determined and used to calculate the percent mass of acetic acid in Barney's Brew. Calculations of percent mass should be organized and follow-able;  short annotations must precede each calculation step. Attention should be given to significant digits and units. The Conclusion should use a single sentence to state the answer to the question posed in the Purpose.











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