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Calculate the mass percent of Cu(NO3)2 (MM=187.56 g/mol) in a 0.450 M solution. d=1.110g/mL To receive full credit (2 pts for answers and 1 pt for showing work), submit a picture of your work to the Final Exam Required Work & Partial Credit  assignment AFTER SUBMITTING COMPLETED FINAL

Consider the data table below to calculate the enthalpy of reaction for the neutralization of nitric acid by barium hydroxide.   Volume of 1.242MHNO3,  mL 50.00 60.00 70.00 80.00 90.00 100.0 Volume of 0.6521MBa(OH)2, mL 100.0 90.00 80.00 70.00 60.00 50.00 Change of temperature, oC 4.74 5.65 6.66 7.67 6.34 5.16 Analyze the Data Table to find the highest temperature and answer the following questions. Consider the density of the solutions to be the same as water, 1.00 g/mL, both before and after mixing, and the heat capacity is the same as for water, 4.18J/oCg.  Since your calculators may give you slightly different numbers, pick the closest answer. The highest temperature change in oC[temp]  Number of moles of acid  at the highest temperature (at stoichiometric ratio)[molesA] Number of moles of the base  at the highest temperature (at stoichiometric ratio)[molesB] Mole fraction of acid and mole fraction of base at the highest temperature (at stoichiometric ratio)[MF] Stoichiometric mole ratio for the reaction: moles acid/moles base, calculated [MR] Stoichiometric mole ratio for the reaction: moles acid/moles base, rounded to the whole number[MR2] Heat absorbed by the solution in the calorimeter, J[q] Heat in kJ produced by the reaction between solutions of acid and base in the calorimeter[q2] Heat of reaction in kJ per number of moles of base[H] Thermochemical equation and Enthalpy  of the neutralization reaction (Hint: Enthalpy is per number of moles of water)[Eq] To receive full credit (10 pts for answers and 5 pts for showing work), submit a picture of your work to the Final Exam Required Work & Partial Credit  assignment AFTER SUBMITTING COMPLETED FINAL

Write and balance the molecular equation for the complete neutralization of H3PO4 by NH4OH. What is the molar ratio of acid to base (stoichiometric factor)? To receive full credit (2 pts for answers and 2 pts for showing work), submit a picture of your work to the Final Exam Required Work & Partial Credit  assignment AFTER SUBMITTING COMPLETED FINAL

1. The following table was filled by the student during the measuring of the absorbance of a 100 mM solution of Ni2+ ion. Wavelength Absorbed (nm) Color Absorbed Color Observed Absorbance of solution 410 Violet Yellow-Green 0.23 430 Blue-Violet Yellow 0.52 480 Blue Orange 0.07 500 Blue-Green Red 0.03 530 Green Purple 0.01 560 Yellow-Green Violet 0.01 580 Yellow Blue-Violet 0.01 610 Orange Blue 0.03 680 Red Blue-Green 0.16 720 Red-Purple Green 0.19 Select a correct wavelength to measure the absorbance of nickel-containing solutions and justify your answer below, 4pts 2. The following calibration table was built in order to calibrate the colorimeter: Blank 0.000 0.00 Test tube 1 0.020 0.10 Test tube 2 0.040 0.26 Test tube 3 0.060 0.37 Test tube 4 0.080 0.42 Test tube 5 0.100 0.53 Test tube 6 0.120 0.68 Test tube 7 0.140 0.72 Test tube 8 0.160 0.88 Test tube 9 0.180 0.98 Test tube 10 0.200 1.20 Report the equation of the trendline in terms of Absorbance, Molarity and molar absorptivity (you do not need to show the graph) and the value of R2(6pts, report your answer below) 3. The 18.0 g sample of Zn-Ni alloy was dissolved in the nitric acid and diluted to 250.0 mL. The measured absorbance of the solution was 0.77. Use the calibration curve equation to calculate and report:Molarity of the solution (3 pts, report your answer below) %Ni in the alloy (3 pts, report your answer below) To receive credit, report your answers below and submit a picture of your work to the Final Exam Required Work & Partial Credit  assignment AFTER SUBMITTING COMPLETED FINAL ANSWERS:

Build the Lewis dot structure of the molecule BrOCl3 and answer the following questions: 1. What is the shape of the molecule?[Molec] 2. What is(are) the possible value(s) of angles Cl-Br-Cl?[Angle] Save and upload your Lewis dot structures to the “Calculations and Partial Credit on Midterm Exam” assignment to earn one (2) more points after you submit this exam. Be sure to number your answers and use the correct units.

What is the molecular shape of CO2?    Build the Lewis dot structure of the molecule  CO2 and answer the following questions: 1. What is the general electron domain formula for this molecule  (AXmEn)? [Formula] 2. What is the electron domain geometry of the molecule? (Hint: electron geometry is not always the same as the molecular shape).[Elec] 3. What is the electron shape of the molecule?[Molec] Save and upload your Lewis dot structures to the “Calculations and Partial Credit on Midterm Exam” assignment to earn one (2) more points after you submit this exam. Be sure to number your answers and use the correct units.  

Build the Lewis dot structure of the molecule  SOF2 and answer the following questions: 1. How many electron domains surround the central atom?[Domain] 2. What is the electron domain geometry of the molecule? (Hint: electron geometry is not always the same as the molecular shape).[Shape] 3. What is the value of O-S-O bond angles?[Angles] Save and upload your Lewis dot structures to the “Calculations and Partial Credit on Midterm Exam” assignment to earn one (2) more points after you submit this exam. Be sure to number your answers and use the correct units.

Build the Lewis dot structure of the molecule  KrF2 and answer the following questions: What is the  shape of the molecule? Is it polar? Save and upload your Lewis dot structures to the “Calculations and Partial Credit on Midterm Exam” assignment to earn one (1) more point after you submit this exam. Be sure to number your answers and use the correct units.  

Build the Lewis dot structure of the molecule and answer the following questions: How many sigma bonds, pi bonds and nonbonding domains, respectively, can be associated with I in the molecule of IOF3? Save and upload your Lewis dot structures to the “Calculations and Partial Credit on Midterm Exam” assignment to earn one (1) more point after you submit this exam. Be sure to number your answers and use the correct units.  

Build the Lewis dot structure of the molecule  PBrCl2 and answer the following questions: 1. What is the shape of the molecule?[Molec] 2. What is the value of angle Cl-P-Cl?[Angle] Save and upload your Lewis dot structures to the “Calculations and Partial Credit on Midterm Exam” assignment to earn one (2) more points after you submit this exam. Be sure to number your answers and use the correct units.