For part A B & C do calculations and write the missing numbers in the tables Part D Application of Hess's Lawa. Write in your experimentally-derived enthalpy values in the followingthermochemical equations.(1) Mg(s) + 2 HCl(aq) → MgCl₂(aq) + H₂(g)(2) Mg0(s) + 2 HCl(aq) → MgCl₂(aq) + H₂O(1)AH₁ΔΗ, =AH3 =b. Use Hess's Law to get AH3 for reaction (3) from AH₁ and AH₂.Mg(s) + H₂O(1)→ MgO(s) + H₂(g)(3)c. Now calculate AH3 from standard molar enthalpies of formation found in thethermodynamic tables in the appendix.d. Discussion: Compare your experimental value of AH3 with the value calculatedfrom the thermodynamic tables. Can you explain why they shouldn't be exactlythe same? Part A. Calorimeter ConstantTrialsTemp. of 50.0 mL cool water (Tc)Temp.of 50.0 mL warm water (Th)Max. temp on mixing (T₂)Heat capacity of calorimeter (J/°C)Average heat capacity of cal. (J/°C)Show a sample calculation of the heat capacity of the calorimeter for one run. Show bothvalues and the aveage in the table above. In the calculations for Parts B and C, use Ccal =0 if your average heat capacity is negative.Part B Mg plus HC1TrialsMass of magnesiumInitial temp. of HC1 (T₁)Final (max.) temp. (T₂)AT = T₂-T₁AH (kJ/mol Mg)Average value of AH(kJ/mol Mg)Part C MgO plus HC1TrialsMass of weighing dish plus MgOMass weighing dish after useNet mass of MgO taken for reaction118.8°C80.0°C52.8°CInitial temp. of HC1 (T₁)Final (max.) temp. (T₂)10.1496919.4°C35.1°C10.818290.5691923.018.5°CAT = T₂-T₁AH (kJ/mol MgO)Average value of AH(kJ/mol MgO)In your notebook show a sample calculation of the heat of reaction for one run for parts Band C. Show both values and the average in the tables above. Assume 50.0g, withCsolution 4.18 J/gºC.

The enthalpy of reaction, ΔH0rxn is: ΔH0rxn= ΔH0f(products)- ΔH0f(reactants)

Part D Application of Hess's Law a. Write in your experimentally-derived enthalpy values in the following thermochemical equations. (1) Mg(s) + 2 HCl(aq) → MgCl₂(aq) + H₂(g) (2) Mg0(s) + 2 HCl(aq) → MgCl₂(aq) + H₂O(1) ΔΗ, ΔΗ2 = b. Use Hess's Law to get AH3 for reaction (3) from AH₁ and AH2. (3) Mg(s) + H₂O(1)→ MgO(s) + H₂(g) AH3 = c. Now calculate AH3 from standard molar enthalpies of formation found in the thermodynamic tables in the appendix.

Part D Application of Hess's Law a. Write in your experimentally-derived enthalpy values in the following thermochemical equations. (1) Mg(s) + 2 HCl(aq) → MgCl₂(aq) + H₂(g) (2) Mg0(s) + 2 HCl(aq) → MgCl₂(aq) + H₂O(1) ΔΗ, ΔΗ2 = b. Use Hess's Law to get AH3 for reaction (3) from AH₁ and AH2. (3) Mg(s) + H₂O(1)→ MgO(s) + H₂(g) AH3 = c. Now calculate AH3 from standard molar enthalpies of formation found in the thermodynamic tables in the appendix.

Chemistry for Engineering Students

4th Edition

ISBN:9781337398909

Author:Lawrence S. Brown, Tom Holme

Publisher:Lawrence S. Brown, Tom Holme

Chapter9: Energy And Chemistry

Section: Chapter Questions

Problem 9.94PAE

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