Question

In: Chemistry

Consider the following reaction: 2Mg(s)+O2(g)→2MgO(s) ΔH=−1204kJ Calculate the amount of heat transferred when 3.55 g of...

Consider the following reaction: 2Mg(s)+O2(g)→2MgO(s) ΔH=−1204kJ

Calculate the amount of heat transferred when 3.55 g of Mg(s) reacts at constant pressure ΔH= kJ

Solutions

Expert Solution

Given :

2 Mg (s) + O2 (g) --- > 2 MgO (s)       Delta H = -1204 kJ

Mass of Mg = 3.55 g

Calculation of moles of Mg =3.55 g / molar mass of Mg

= 3.55 g / 24.305 g per mol

= 0.1523 mol

Given reaction shows that when 2 mol Mg reacts heat transferred = 1204 kJ

Lets calculate the heat for 3.55 g Mg

Heat transferred = 0.1523 mol Mg x -1204 kJ/2 mol Mg

= -91.70 kJ

Second part :

Calculation of mass of Mg

Moles of Mg = -231 kJ x 2 mol / -1204 kJ

= 0.3837 mol Mg

Mass of Mg = 0.3837 mol Mg x 24.305 g per mol

= 9.33 g

Third part :

The decomposition of MgO (s) is reverse reaction to the given.

Delta H for reverse reaction has only sign difference.

Reaction :

MgO(s) ----- >2Mg(s)+O2(g)       ΔH=1204kJ

Heat absorbed = 40.6 g MgO x 1 mol MgO / molar mass of MgO ) x( 1204 kJ/2 mol)

= 40.6 g x (1 mol MgO / 40.304 g per mol) x 1204 kJ/ 2 mol MgO

= 606.4 kJ

Heat absorbed will be = 606.4 kJ


Related Solutions

Consider the following reaction: 2Mg(s)+O2(g)→2MgO(s)ΔH=−1204kJ Calculate the amount of heat transferred when 3.54 g of...
Consider the following reaction:2Mg(s)+O2(g)→2MgO(s)ΔH=−1204kJCalculate the amount of heat transferred when 3.54 g of Mg(s) reacts at constant pressure.How many grams of MgO are produced during an enthalpy change of -237 kJ ?How many kilojoules of heat are absorbed when 40.1 g of MgO(s) is decomposed into Mg(s) and O2(g) at constant pressure?
Consider the following reaction: 2Mg(s)+O2(g)→2MgO(s)ΔH=−1204kJ Part A Is this reaction exothermic or endothermic? exothermic endothermic SubmitMy...
Consider the following reaction: 2Mg(s)+O2(g)→2MgO(s)ΔH=−1204kJ Part A Is this reaction exothermic or endothermic? exothermic endothermic SubmitMy AnswersGive Up Correct Part B Calculate the amount of heat transferred when 3.56 g of Mg(s) reacts at constant pressure. ΔH =   kJ   SubmitMy AnswersGive Up Part C How many grams of MgO are produced during an enthalpy change of -231 kJ ? m =   g   SubmitMy AnswersGive Up Part D How many kilojoules of heat are absorbed when 40.7 g of MgO(s) is...
1. For the reaction: 2Mg(s) + O2(g) → 2MgO Calculate the percent yield if 10g of...
1. For the reaction: 2Mg(s) + O2(g) → 2MgO Calculate the percent yield if 10g of Mg and 15g of O2 react, and 15.0g MgO was actually obtained. 2. For the reaction: H2(g) + Cl2(g) → HCl(g) (is this balanced?) calculate the mass, in grams of Hydrogen Chloride produced when H2 reacts with 25.0g Cl2.
Refer to the reaction 2Mg + O2---> 2MgO starting amounts 1.25mg 2Mg, and 25g of O2....
Refer to the reaction 2Mg + O2---> 2MgO starting amounts 1.25mg 2Mg, and 25g of O2. What are the changes that occur in this reaction as its happening? Complete an ice table using the starting amounts and referring to the reaction above. *I have no idea how to do these, in the words of Micheal Scott, "Why don't you explain this to me like I'm 5 years old."*
Using the equation shown below, 2Mg(s)+ O2(g)>>> 2MgO(s) When 10.1g Mg reacts with 10.5g of O,...
Using the equation shown below, 2Mg(s)+ O2(g)>>> 2MgO(s) When 10.1g Mg reacts with 10.5g of O, 11.9g of the product was collected. Determine the limiting reactant, theoretical yield, percent yield and the remaining excess reactant from the reaction.
Part 1. Consider the following reaction at 298 K: 2H2(g)+O2(g)---->2H2O(g) ΔH=-483.6 kj/mol Calculate the following quantities:...
Part 1. Consider the following reaction at 298 K: 2H2(g)+O2(g)---->2H2O(g) ΔH=-483.6 kj/mol Calculate the following quantities: ΔSsys=____J(molxK) ΔSsurr=____J(molxK) ΔSuniv=____J (molxK) Part 2. For a particular reaction, ΔH = 168.1 kJ/mol and ΔS = -55.8 J/(mol·K). Calculate ΔG for this reaction at 298 K. Is this system spontaneaus as written, Is it in the reverse direction, Or is it at equilibrium?
Part A) Calculate ΔHrxn for the reaction CaO(s)+CO2(g)→CaCO3(s) given these reactions and their ΔH values: Ca(s)+CO2(g)2Ca(s)++12O2(g)O2(g)→→CaCO3(s),2CaO(s),ΔH=−814.1...
Part A) Calculate ΔHrxn for the reaction CaO(s)+CO2(g)→CaCO3(s) given these reactions and their ΔH values: Ca(s)+CO2(g)2Ca(s)++12O2(g)O2(g)→→CaCO3(s),2CaO(s),ΔH=−814.1 kJΔH=−1269.8 kJ Express the enthalpy in kilojoules to one decimal place. Part B) Calculate Δ Hrxn for the following reaction: CH4(g)+4Cl2(g)→CCl4(g)+4HCl(g) given these reactions and their ΔH values: C(s)C(s)H2(g)+++2H2(g)2Cl2(g)Cl2(g)→→→CH4(g),CCl4(g),2HCl(g),ΔH=−74.6 kJΔH=−95.7 kJΔH=−184.6 kJ Express the enthalpy in kilojoules to one decimal place. Part c) The thermite reaction, in which powdered aluminum reacts with copper oxide, is highly exothermic. 2Al(s)+3CuO(s)→Al2O3(s)+3Cu(s) Use standard enthalpies of formation to...
Calculate ΔHrxn for the following reaction: CaO(s)+CO2(g)→CaCO3(s) Use the following reactions and given ΔH′s. Ca(s)+CO2(g)+12O2(g)→CaCO3(s), ΔH=...
Calculate ΔHrxn for the following reaction: CaO(s)+CO2(g)→CaCO3(s) Use the following reactions and given ΔH′s. Ca(s)+CO2(g)+12O2(g)→CaCO3(s), ΔH= -812.8 kJ 2Ca(s)+O2(g)→2CaO(s), ΔH= -1269.8 kJ Express your answer using four significant figures. Please help I keep getting all the wrong answers.
From the enthalpies of reaction H2(g)+F2(g)→2HF(g)ΔH=−537kJ C(s)+2F2(g)→CF4(g)ΔH=−680kJ 2C(s)+2H2(g)→C2H4(g)ΔH=+52.3kJ calculate ΔH for the reaction of ethylene with...
From the enthalpies of reaction H2(g)+F2(g)→2HF(g)ΔH=−537kJ C(s)+2F2(g)→CF4(g)ΔH=−680kJ 2C(s)+2H2(g)→C2H4(g)ΔH=+52.3kJ calculate ΔH for the reaction of ethylene with F2: C2H4(g)+6F2(g)→2CF4(g)+4HF(g)
From the enthalpies of reaction H2(g)+F2(g)→2HF(g)ΔH=−537kJ C(s)+2F2(g)→CF4(g)ΔH=−680kJ 2C(s)+2H2(g)→C2H4(g)ΔH=+52.3kJ calculate ΔH for the reaction of ethylene with...
From the enthalpies of reaction H2(g)+F2(g)→2HF(g)ΔH=−537kJ C(s)+2F2(g)→CF4(g)ΔH=−680kJ 2C(s)+2H2(g)→C2H4(g)ΔH=+52.3kJ calculate ΔH for the reaction of ethylene with F2: C2H4(g)+6F2(g)→2CF4(g)+4HF(g)
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT