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Lab Report On The Enthalpy Of Neutral Essay

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Purpose: To utilize a calorimeter correctly to find the enthalpy changes in two different reactions. The purpose was also to use concepts of specific heat to observe the relationship between temperature observations and heat transfer. Then, use the equations to see the relationship between change in energy and the amount of substance involved. Use Hess’ law to determine the change in energy.

Procedure: Refer to pages 67-76 of General Chemistry 1210: General Chemistry Laboratory Manual by the Department of Chemistry, The Ohio State University, Hayden-McNeil Publishing, 2016.

Data/ Results: See attached report sheets

Sample Calculations:
Value of heat capacity
〖-(q〗_cu+q_water)=q_calorimeter
q=C_s*m*ΔT q_water=58.7150g*4.18J/(g*˚C)*7.9˚C q_calorimeter=-(-1950+1938)=12.0
Molar enthalpy of neutral
ΔH_1=q_rx1/moles=-65800J/mole
-q_rx1=q_HCl+q_NaOH+q_calorimeterl=1870J+59.5J+90J=2000J
Heat of rxn of Mg2+ and acid
-q_rx1=q_Soln+q_calorimeter=2270J+122J=2390J
ΔH3 ,
Mg(s) + 2H+(aq) →Mg2+(aq) + H2(g) 65.8kj/mole
〖〖2H〗_2 O(l)→2H〗^+ (aq)+〖2OH〗^- (aq) -362kj/mole

Mg(s) + 2 H2¬O(l) → Mg2+(aq) + 2OH¬-(aq)+ H2(g) -296kj/mole

ΔH4
Mg2+(aq) + 2OH¬-(aq)+ H2(g) →Mg(s) + 2 H2¬O(l) 296kj/mole
Mg(s) + O2(g) +H2(g) →MgOH2(s) -924.7kj/mole
2H2O(l) → 2H2(g) + O2(g) 571.6kj/mole

Mg2+(aq) + 2OH¬-(aq) →MgOH2(s) -57kj/mole Discussion/ Conclusions: The lab used methods of calorimetry in order to measure the temperature change of reactions and calculate the changes in

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