1. Lab #6 AP chem. WHAT’S IN THE BOTTLE?
An Inquiry Lab

2. PRESENTATION:
You will need a binder paper and a ruler (for data tables)
Construct your paper in the order of Pre-Lab
Lab
Procedures
Data tables
Post lab

3. GOAL
To determine the type of bonding in unlabeled chemicals using physical and chemical properties of substances with ionic, molecular, and metallic bonds.

4. IONIC COMPOUNDS(Notes)
compounds containing a metal and a nonmetal strong electrostatic attractions between positive and negative ions
formulas given in the simplest ratio of elements
crystalline structures that are solids at room temperature
ions that form a crystal lattice structure.
compounds that melt at high temperatures
Substances that are good conductors of electricity in the molten or dissolved state

5. COVALENT COMPOUNDS(notes)
nonmetals attracted to other nonmetals
formulas that are given in the true ratios of atoms
substances that may exist in any state of matter at room temperature (solid, liquid, or gas)
compounds that melt at low temperatures
substances that are nonconductors of electricity

6. Polar versus nonpolar(Notes)
Polar Covalent - NM/NM or M/NM
usually dissolves in water
Usually higher in mass than nonpolar substances
More likely to be solids.
Nonpolar Covalent – NM/NM
Does not dissolve in water
Usually not solids.

7. Metallic compounds (notes)
substances that are metals
a “sea” of mobile or delocalized electrons surrounding a positively charged metal center
an attraction between metal ions and surrounding electrons
formulas written as a neutral atom (Mg, Pb)
solids with a crystalline structure at room temperature
a range of melting points—usually depending on the number of valence electrons
substances that are excellent conductors of electricity since the electrons in the “sea” are free to move.

8. SAFETY AND DISPOSAL
Safety goggles should be worn at all times in the laboratory.
Be cautious of acidic and basic solutions since they can cause skin burns and eye damage.
Liquids and solids are to be disposed of in properly labeled waste containers per MSDS guidelines.
Galvanized iron square has sharp edges – handle with care to prevent cuts.

9. MATERIALS
Universal indicator, 0.1M hydrochloric acid (HCl), 0.1M sodium hydroxide (NaOH), 70 % Ethanol(C2H5OH); Ice, Magnifying lens, micro- scale wellplate, Hexane, Phenolphthalein, Conductivity tester (metals and aqueous only), Distilled water, pH paper, wooden splints, food can lid (iron circle), cotton swabs, MSDS for all knowns and unknowns used, toothpicks, magnet, sandpaper, hot plate.

10. Pre-lab Preparation
You will be given 4-6 KNOWN chemicals (1–10 grams each) in small containers.
The containers are labeled with the name & formula
CAS number not included.
A CAS # is(Chemical Abstracts Service) Registry Number is a unique identifier that tells you, for example, that acetone and dimethyl ketone are actually the same substance.

11. PRELAB GUIDED QUESTIONS
Review the electronegativities of the elements. Review electronegativity values and trends using the periodic table.
Have a discussion with your lab partner(s) about the type of bonding represented by the chemicals in this lab: nonpolar covalent, polar covalent, ionic, and metallic.

13. PRELAB GUIDED QUESTIONS
**Replacing Iodine with STEARIC ACID white solid, MP 67°C, insoluble in water, NM/NM, nonpolar covalent

14. PRELAB GUIDED QUESTIONS
3. Compare the type of bond with regard to the properties below using Table 1 and explain any relationships. HINT: Think of what is happening between the bonded atoms as well as what occurs between the particles.
a. melting point
b. solubility in 25oC water
4. Predict the properties of each substance below based on Table 1.

15. PRELAB GUIDED QUESTIONS: (Copy to your paper)

16. PART ONE Practice with Instrumentation and Procedure
The purpose of this portion of the lab is to identify properties that allow one to determine the type of bonding in a substance and to carry out tests that allow one to characterize these properties.

17. PROCEDURE
Given four known compounds, choose at least four different tests to study physical and chemical properties of each of the given substances.
Based on your results, you will develop a system that will help determine whether an unknown solid is ionic, covalent (polar or nonpolar), or metallic using these tests.
Possible tests include: color, solubility in water, conductivity of the solid, conductivity in water, pH of the solution in water, solubility in ethanol, solubility in hexanes, high/low melting point (order of melting if qualitative), reaction with 0.1M HCl, reaction with 0.1M NaOH, and magnetism.

18. PROCEDURE
Select at least four tests, quantitative and qualitative, and write a detailed procedure to carry out the tests.
Refer to the Materials section for guidance on available materials.
Create a data table to record results.
Performs tests
Melting point will be done qualitatively using a can lid to compare relative melting time.

19. NEXT
Once you finish Part One, turn in the four containers – potassium chloride, sucrose, zinc, and Iodine.
You will pick up your five unknowns.
You are responsible for returning your unknowns to cart.

20. Practice Questions
Will be given to you !!!

21. Part Two The Investigation Procedure
The knowledge acquired in the Practice section for known compounds will now be applied in order to determine the type of bond for five unknown solids. Given five unknown compounds, you will choose at least four different tests to study physical and chemical properties of the substances. Based on your results, you will develop a system that will help determine whether an unknown solid is ionic, covalent (polar or nonpolar), or metallic using these tests. Possible tests include color, solubility in water, conductivity of the solid, conductivity in water, pH of the solution in water, solubility in ethanol, solubility in hexanes, high/low melting point (order of melting if qualitative), reaction with 0.1 M HCl, reaction with 0.1 M NaOH, and magnetism.
You should select at least four tests, quantitative and qualitative, and write a detailed procedure to carry out the tests. Refer to the Materials section for guidance on available materials.

22. Data Collection and Computation
Create a data table to record results. After you have completed your procedure, complete data table. Identify the bond type in each unknown. Using the list of all of the unlabeled bottles (the unknowns), your results, and the MSDS for the unknowns, identify the five chemicals you tested.

23. CONCLUSION (Will be given to you!!!) Argumentation and Documentation
Answer the questions that follow.
Post lab Assessment

24. HELPFUL HINTS Everything you need is at the material cart:
Cotton swabs, extra toothpicks, and extra splints are on the back table.
Chemicals on trays on back table are NOT for this lab.
Ice
Unknowns must turn in four knowns before getting unknowns.
Return unknowns to cart each day.
Unplug hot plate before leaving for the day.

25. GET STARTED Wear goggles Get your unknowns from the front.
If you need the four knowns from yesterday, get them from cart.

26. POTENTIAL Unknown COMPOUNDS
The list will be given to you in class.