Guide Study For Chem 101L Final Exam 1. Names, uses, and differences of Chemical Glassware Erlenmeyer flask vs. a side-arm flask Volumetric pipette vs. graduated pipette Volumetric flask vs. graduated cylinder vs. beaker Burette, cuvette, pipette, etc. Recognize and identify glassware near front of manual (pg. vii, viii) 2. Safety rules & guidelines from lab and manuals What clothing is appropriate/inappropriate? What do you do if you catch on fire? Something else catches on fire? Something gets in your eye? Etc. Why should you not wear contacts in lab? 3. Review all pre-lab lectures & try last year's learning devices (available by download on blackboard) Experiment 1: Nothing, as far as I can tell Experiment 2: Scientific Measurment and Error Precision Accuracy Experimental Error Systematic/Determinate Error Random/Indeterminate Error Significant Figures Gaussian/Normal Distribution Mean/Average Standard Deviation Degrees of Freedom Reproducibility Q-test Analytical balance Weighing boat, crucible, weighing bottle Weighing by difference Burette Surface Tension Meniscus Graduated Cylinder Disposable Pipette Know the difference between TC and TD glassware, their uses, and why the difference exists Know how to calculate the mean, standard deviation, and how & when to apply the Q-test Know how to use an analytical balance, a burette, and a pipette Know how to read a burette & graduated pipette Be able to look at the mean & standard deviation of a data set and draw conclusions about the precision and accuracy of the experiment Mouth pipetting is NEVER permitted Any unused solution must NEVER be returned to the reagent bottle
Experiment 3: PASCO sensors & Chemical Reactions Dissolution Solubility Solute-Solute, Solute-Water, & water-water interactions Coulombic Attraction Hydrated Hydration Energy vs. Lattice Energy Hydronium Ion Acid Base Spectator Ions Precipitation Rxn Acid-Base Rxn Gas-forming Rxn Complexation Rxn Covalent Bond Endothermic Rxn Exothermic Rxn Know Solubility Rules Know about pH sensor Know about conductivity sensor Know about colorimeter Be able to look at a reaction and define it as acid-base, precipitation, gas-forming, etc. Be very comfortable with concepts of Endothermic & exothermic reactions Be able to write and balance net ionic equations Given a graph of pH vs time, be able to calculate change in pH per unit time Explain why dissolving salts is usually an endothermic process Explain why some dissolution processes are exothermic
Experiment 4: Mass, Volume, & Density Density Intensive vs. Extensive Properties Room Temperature (in C or K)
When do you plug-in/unplug an immersion heater? Why was the error so substantial for this experiment? (Hint: consider the accuracy and precision of the equipment compared to the necessary precision to measure the change in the density of water as a function of temperature) Know the equation for density Know how to calculate density if given a volume and a mass (which is just as easy as it sounds if you have the units for the above equation)
Experiment 5: Conductometric Titration Stoichiometry Balanced Equation Conservation of Matter Reaction Chemical Cations, Anions Electrolyte Conductor/Conductivity Resistivity Ohm/Siemens Titration Dessicator/Dessicant What does the phrase "conductometric titration" really mean? Review (from Lab 3) the conductivity sensor How do you use a dessicator? Understand the concept of "Conservation of Matter" and how it applies to chemical reactions Understand the rationale behind doing a gross trial, then several fine trials Given a graph of conductivity vs volume, be able to determine the minimum conductivity via linear regression (understand the concepts required, not the specific steps you used on data studio) and know how to calculate the number of moles of titrant required to obtain this minimum Practice Balancing Reactions Be able to determine the number of moles of one particular element, given the concentration of a molecule partially composed of that element. Given the mass of two elements, determine the moles of each, and find the molar ratio
Experiment 6: Spectroscopy Energy Level Transitions Emission Adsorption Wave Theory White Light Balmer Series Balmer Equation Niels Bohr Bohr Model Ground state Spectroscope Diffraction Grating Electrical discharge Tube Atomic Emission Spectrum Continuous Emission Spectrum How is energy/light emitted from a substance? (i.e. what are the electrons doing?) Given a calibration curve, be able to convert observed position to wavelength and vice-versa. Be able to convert wavelength into frequency. Be able to calculate Energy from frequency. Given a wavelength (or a position and a calibration curve, or a frequency, or an energy) be able to convert into energy level transitions using the Balmer equation Know the transitions that correspond to white light Understand "soft" vs. "harsh" light and the relationship between color, wavelength, frequency, and energy. Understand the answers from the homework questions
Experiment 7: Thermochemistry Thermochemistry Changes of Physical State Thermal Energy First Law of Thermodynamics (Law Of Energy Conservation) System Surroundings Heat Work Joule Enthalpy Heat of Reaction Standard Enthalpy Change Standard heat of Formation Hess's Law State Function Calorimetry/Calorimeter Heat Capacity Specific Heat Know how to apply Hess's Law, given reactions and H's. Know the two practical problems associated with using a calorimeter and how they are fixed Know how and why you used a cooling curve and why you put on two regressions Be able to calculate qsoln, qcal, and qrxn. Given the appropriate data, be able to calculate the calorimeter constant
Experiment 8: Beer's Law Beer's Law Colorimetry Pyrolysis Colorimeter Transmitted light Absorbed Light Cuvette Photodiode Limiting reagent Know equations for Beer's Law and Absorbance Know what the variables in both of those equations are. Know how to calculate the volume of stock solution necessary to be diluted to obtain a specific concentration (M1V1 = M2V2) Be able to determine the mg of iron per 100 g of food Use Beer's Law to determine concentration of a substance in solution Be able to convert from concentration to mol's and grams, provided the appropriate information