What is the molarity of the hydrochloric acid if the student used 41.25 mL of 0.1145M standard solution of NaOH to titrate 20.00 mL of acid to the endpoint? 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

Write and balance the equation and determine the mole ratio of reactants. Use this information to answer the following questions: How many moles of NaOH are present in 255 mL of 2.7471M solution? How many moles of H3PO4 are needed to completely neutralize this base? 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

Apply the Hess’s Law and use the Data table below to calculate the ΔH°rxn, in kJ, for: Ca(OH)2(s) + 2HCl(aq) => CaCl2(aq) + 2H2O(l) To receive full credit (3 pts for MC 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 Substance ΔH°f,kJ/mol Ca(OH)2(s) −985 HCl(aq) −166 CaCl2(aq) −879 H2O(l) −286

Write and balance the equation and determine the mole ratio of reactants. Use this information to answer the following questions: How many moles of Ca(OH)2 are present in 250.0 mL of a 0.7995M solution? How many moles of HBr are needed to completely neutralize this base? 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

A  container holds 50.0 mL of nitrogen at 22.0° C and a pressure of 736 mm Hg. What will be its volume in mL if the temperature increases to 35.0° C at the same pressure? To receive full credit (2 pts for answers and 1 pts for showing work), submit a picture of your work to the Final Exam Required Work & Partial Credit  assignment AFTER SUBMITTING COMPLETED FINAL

  Apply the Hess’s Law and use the Data table below to calculate the ΔH°rxn, in kJ, for: Sr(OH)2(s) + 2HNO3aq) => Sr(NO3)2(aq) + 2H2O(l) To receive full credit (3 pts for MC 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 Substance  ΔHf° (kJ mol–1) Sr(OH)2(aq) -1007 HNO3(aq) -207 Sr(NO3)2(aq) -962 H2O (l) -286  

Calculate the number of moles of AgNO3 (MM=169.87 g/mol) in 250.0mL of 0.200 M solution To receive full credit (3 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

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:

Which of the following explains why different metals produce different colors during the flame test?

Build the Lewis dot structure of the molecule  IF4- and answer the following questions: Save and upload your Lewis dot structures to the “Calculations and Partial Credit on Midterm Exam” assignment to earn one point after you submit this exam. Be sure to number your answers and use the correct units.