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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 0.7471M solution?[N] How many moles of H2SO4 are needed to completely neutralize this base?[S] 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

What is the molarity of the hydrochloric acid if the student used 39.25 mL of 0.1252M 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

How many grams of AgNO3 (MM=169.87 g/mol) were used to prepare 250. mL of a solution that is 0.140M?   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

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?[A] How many moles of H3PO4 are needed to completely neutralize this base?[B] 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

Consider the data table below to calculate the enthalpy of reaction for the neutralization of nitric acid by barium hydroxide.   Volume   of 1.021MHNO3,  mL 50.00 60.00 70.00 80.00 90.00 100.0 Volume of 0.572MSr(OH)2, mL 100.0 90.00 80.00 70.00 60.00 50.00 Change of temperature, oC 4.54 5.45 6.36 7.27 6.54 5.46 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

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