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Why the temperature remains constant during the phase changes? 

  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) Show work for Partial Credit: take a picture of your work, save it to your Canvas files, and upload your answer in the Work and Calculations assignment provided. Substance  ΔHf° (kJ mol–1) Sr(OH)2(aq) -1007.3 HNO3(aq) -206.63 Sr(NO3)2(aq) -962.32 H2O (l) -285.83  

If 20.0 mL of 0.200 M Ca(OH)2reacted with 0.200 M HC2H3O2, what volume of acetic acid is required to neutralize the base?           Hint: write the balanced equation first

16.00 ml of 0.50 M HCl reacts with 6.00 mL of 0.50 M Ba(OH)2 in a stoichiometry study using the methods of continuous variations. The stoichiometry of the system was shown by the following balanced equation: Ca(OH)2(aq) + 2HCl(aq) → CaCl2(aq) + 2H2O(l) On the basis of the limiting reagent, calculate the theoretical number of moles of product (BaBr2) that should have been formed.

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]

Balance the following reaction and determine the coefficient for water. __H2SO4(aq) + __Fe(OH)3(s) → __Fe2(SO4)3(aq) + __H2O(l)

A sample of gas occupies a volume of 160.0 L at 155° What will be the volume of gas in mL when the temperature drops to 55° C at the same pressure?

What is the percent yield of a reaction if the product recovered is 89.4 g and the theoretical yield is 128.4 g?

Consider the following reaction: NaCl(aq) + AgNO3(aq) => AgCl(s) + NaNO3(aq)  In order for the gravimetric analysis to provide the valid results  we want all of the chloride ions to precipitate. How can we ensure this?

Consider the titration process according to the reaction below Ba(OH)2(aq) + 2HBr(aq) => BaBr2(aq) + 2H2O(l) What is pH at the equivalence point?