Enthalpy H is a measure of the energy content of a system atconstant pressure. Chemical reactions involve changes in enthalpy,ΔH, which can be measured and calculated:ΔHrxn∘=∑productsmΔHf∘−∑reactantsnΔHf∘ where the subscript \"rxn\" isfor \"enthalpy of reaction\" and \"f\" is for \"enthalpy of formation\"and m and n represent the appropriate stoichiometric coefficientsfor each substance. The following table lists some enthalpy offormation values for selected substances. Substance ΔHf∘ (kJ/mol)NaOH(aq) −469.1 MgCl2(s) −641.8 NaCl(aq) −407.3 Mg(OH)2(s) −924.5H2O(l) −285.8 Part A Determine the enthalpy for this reaction:MgCl2(s)+2NaOH(aq)→Mg(OH)2(s)+2NaCl(aq) Express your answer inkilojoules per mole to one decimal place. ΔHrxn∘ = kJ/mol SubmitMyAnswersGive Up Part B Consider the reactionMg(OH)2(s)→MgO(s)+H2O(l) with enthalpy of reactionΔHrxn∘=37.5kJ/mol What is the enthalpy of formation of MgO(s)?Express your answer in kilojoules per mole to one decimal place.ΔHf∘ = kJ/mol Submit
