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July 23, 2014

Search: Using enthalpies of formation in Appendix C, calculate delta H for this reaction. 2al(s)+Fe2o3(s)-->al2o3(s)+2fe(s)

Number of results: 36,736

chemistry
Calculate the heat of formationof benzene if the heat of combustion of benzene is 3260 kj/mol, given the following enthalpies of formation of the product. enthalpies of formation for O2= 0k (element) enthalpies of formation CO2 = -394kj/mol enthalpies of formation H2O= -285 kJ...
July 18, 2011 by priya

chemistry
use standard enthalpies of formation to calculate delta Hrxn for the following reaction. 2H2S(g)+3O2(g)-->2H2O(l)+2SO2(g) express the answer using four significant figures Delta Hrxn = ? kJ
October 25, 2011 by jen

chemistry
use standard enthalpies of formation to calculate delta Hrxn for the following reaction. 2H2S(g)+3O2(g)-->2H2O(l)+2SO2(g) express the answer using four significant figures Delta Hrxn = ? kJ
October 25, 2011 by jen

Chemistry
The balanced equation for the decomposition of sodium bicarbonate is 2 NaHCO3 (s) --> Na2CO3 (s) + H2O (g) + CO2 (g)delta H 129.2. Using the enthalpies of formation, calculate the enthalpy of formation of sodium bicarbonate.
April 30, 2013 by Laura

College Chem
Calculate the enthalpy of reaction from the standard enthalpies of formation of the reactant and product molecules. 2C2H6+7O2-->4CO2+6H20 I am using the back of my book for the standard enthalpies of formation, but cannot seem to find the HoF for C2H6?
May 8, 2011 by Betsie

chemistry
Some spacecrafts use hydrazine (N2H4) as fuel and is burned according to the following reaction: N2H4(l)+N2O4(g)=>2 N2O(g)+2 H2O(g) Calculate the DHrxn for this reaction using the standard enthalpies of formation from Appendix IIB. Calculate your answer to 4 sig figs
March 4, 2013 by Brandi

Chemistry-Enthalpies of formation
"Synthesis gas" is a mixture of carbon monoxide and hydrogen that is used to synthesize a variety of organic compounds. One reaction for producing synthesis gas is 3CH4 + 2H2O + CO2 = 4CO + 8H2 Using enthalpies of formation, calculate the enthalpy change for this reaction in ...
April 13, 2009 by Brigette

chemistry
Which of the following equations represents a reaction for which the delta H can be called a standard enthalpy of formation, delta Hf? a) FeO(s) + CO2(g) -> FeCO3(s) b) 1/2 N2(g) + 2 O(g) -> NO2(g) c) 2 Na(s) + Cl2(g) -> 2 NaCl(s) d) Ba(s) + N2(g) + 3 O2(g) -> Ba(...
January 23, 2012 by timmy

Chemistry
The standard enthalpies of formation of ions in aqueous solutions are obtained by arbitrarily assigning a value of zero to H ions;that is, delta H(f) [H+(aq)]=0 A.for this reaction: calculate delta H(f) for the Cl- ions. HCl(g) ==H2O==>H+(aq)+Cl-(aq) delta H= -74.9 kJ/mol (...
October 31, 2010 by Kristin

Chemistry- college
The standard enthalpies of formation of ions in aqueous solutions are obtained by arbitrarily assigning a value of zero to H ions;that is, delta H(f) [H+(aq)]=0 A.for this reaction: calculate delta H(f) for the Cl- ions. HCl(g) ==H2O==>H+(aq)+Cl-(aq) delta H= -74.9 kJ/mol (...
November 1, 2010 by Willy

Chemistry
Caluclate the delta H for this reaction using standard enthalpies of formation. (The standard enthalpy of formation of liquid pentane is -146.8kJ/mol. Balanced equation balanced equation: C5H12(l)+8O2(g)-->5CO2+6H2O(g) CO2=393.5 H2O=40.7
December 4, 2010 by Ashley

Chemistry
Why do we put a minus sing in front of the bond enthalpies of the bonds that are being formed? And why are the enthalpies of formation negative in general? I also don't understand why we subtract the enthalpy of formation of the reactants from the enthalpy of formation of the ...
April 3, 2010 by Anna

Chemistry
Calculate the enthalpy change of formation for the following reactions using Hess's law, and the enthalpies of formation given in Figure 4: b) MgO +2HCl --> MgCl2 +H2O c)NaOH+ HCl -->NaCl +H20 Figure4: the given enthalpies of formation compound values are: Mg(OH)2 is ...
January 30, 2014 by BOB

Chemistry
Calculate the enthalpy of combustion for acetic acid using standard enthalpies of formation.
November 12, 2012 by Diana

Chemistry
2)Which of the following equations represents a reaction for which the delta H can be called a standard enthalpy of formation, delta Hf? a) FeO(s) + CO2(g) -> FeCO3(s) b) 1/2 N2(g) + 2 O(g) -> NO2(g) c) 2 Na(s) + Cl2(g) -> 2 NaCl(s) d) Ba(s) + N2(g) + 3 O2(g) -> Ba...
January 21, 2012 by Hannah

chemistry
Use standard enthalpies of formation to calculate ΔHrxn for each reaction. (See the appendix. Enter your answer to the tenth place.) (a) 2 H2S(g) + 3 O2(g) 2 H2O(l) + 2 SO2(g) (b) N2O4(g) + 4 H2(g) N2(g) + 4 H2O(g) (c) SO2(g) + 1/2 O2(g) SO3(g) These are so easy, but no ...
November 17, 2012 by DeeDee

Chemistry
Use enthalpies of formation from the textbook to calculate the standard enthalpy of the reaction for the following methane- generating reaction of methanogenic bacteria given delta Hf of CH3NH2=-22.97kJ/mol: 4CH2NH2+2H2O----->3CH4+CO2+4NH3
November 6, 2011 by Kay

Chemistry
Using enthalpies of formation, calculate the quantity of heat produced when 14.0 g of propane is completely combusted in air under standard conditions.
October 14, 2011 by John

Chem
Calculate delta H for the formation of one mole of N2O5 from the elements at 25 degrees C using the following data. 2H2 + O2 - 2H2O delta H = -571.6 kJ N2O5 + H2O - 2HNO3 deltaH = -73.7 kJ 1/2N2 + 3/2O2 + 1/2H2 - HNO3 delta H = -174.1 kJ
April 8, 2010 by Anonymous

chemistry
if enthalpies for formation of p4o10, h2o and h3po4 are -2984, -285.9 and -1279 respectively calculate the enthalpy change using hess's law
July 4, 2012 by mala

Chemistry
Propane (C3H8) burns according to the following balanced equation: C3H8(g)+5O2(g)→3CO2(g)+4H2O(g) Calculate ΔH∘rxn for this reaction using standard enthalpies of formation. (The standard enthalpy of formation of gaseous propane is -103.9 kJ/mol.)
April 6, 2014 by Anonymous

Chemistry(Please check)
1)A piece of metal with a mass of 5.50 grams changed in temperature from 25 to 55 degrees celsius when 21.3 joules was absorbed. What is the specific heat of the metal? a)0.256 b)0.129 c)3.91 d) 7.75 e)0.710 Jg^-1 C^-1 I chose 7.75 because I did 5.50/21.3 and then multiplied ...
January 20, 2012 by Hannah

Chemistry
for the reaction of hydrogen with iodine H2(g) + I2(g) --> 2HI(g) relate the rate of disappearance of hydrogen gas to the rate of formation of hydrogen iodide. and my answer is: rate formation of HI= delta [HI]/delta t and the rate of reaction of I2 = delta [I2]/ delta t to...
February 17, 2008 by Lauren

chemistry
Consider the reaction 3CH4(g)= C3H8(g)+ 2H2(g). Using data from Appendix C in the textbook, calculate delta G at 298 K.
February 14, 2012 by Anonymous

CHEM-HELP!!!!
help? how do i calculate the heat of formation of a solid? i only know how to find the heat of formation of a liquid. here's what i have so far. delta t= 16.8 degrees c mass= 33.136 g cp = 4.184 j/g degrees c m cp delta t = -2329J (process is exothermic) what do i do now?
October 24, 2007 by Jake

Chemistry
Hydrogen and methanol (CH3OH) have both been proposed as alternatives to hydrocarbon fuels. a) Write balanced chemical equations for the complete combustion of hydrogen and the complete combustion of gaseous methanol. Combustion reaction for hydrogen: 2H2(g)+ O2 --> 2H2O(l...
November 4, 2010 by Jarrod

Chemistry
Use standard enthalpies of formation to determine ΔHorxnfor: 3NO2(g) + H2O(l) → 2HNO3(aq) + NO(g) -133.5 = Delta H Find the change in internal energy for this reactioion.. ???? In KJ
February 27, 2014 by Steve

chemistry
Reactions in which a substance decomposes by losing CO are called decarbonylation reactions. The decarbonylation of acetic acid proceeds as follows: CH3COOH(l)= CH3OH(g)+ CO(g. By using data from Appendix C in the textbook, calculate the minimum temperature at which this ...
February 14, 2012 by Anonymous

Chemistry
1. Use standard entropies and heats of formation to calculate delta-G of formation at 25 C for a) cadmium(II) chloride (s) b) methyl alcohol, CH3OH (l) c) copper(I) sulfide (s) My problem is that I don't know how to calculate delta-G of formation. I know that the Gibbs-...
March 4, 2007 by Chris

Chemistry
Mg(s) + 2HCl(aq) -> MgCl2(aq) + H2(g) delta H1? MgO(s) + 2HCl(aq) ->MgCl2(aq) + H2O(l) delta H2? To make these equations add up to the formation reaction of MgO, you will need to include the following: H2(g) + 1/2O2(l) delta H =-241.8 kJ Using Hess's Law and manipulating...
February 14, 2012 by Hannah

chemistry
Many cigarette lighters contain liquid butane, C4H10(l). Using standard enthalpies of formation, calculate the quantity of heat produced when 2.7 g of butane is completely combusted in air under standard conditions.
March 25, 2010 by hello

chemistry
A 114g sample of sucrose undergoes incomplete combustion according to the reaction C12H22011 + 5O2 ---> 4C + 6CO + 2CO2 + 11H2O using the chart of enthalpies of formation determine the enthalpy released by the sample i think that it is a simple enthalpy problem but in the ...
July 25, 2010 by rick

Chemistry
Many portable gas heaters and grills use propane, C3H8(g). Using enthalpies of formation, calculate the quantity of heat produced when 15.0g of propane is completely combusted in air under standard conditions. Assume that liquid water is forming.
October 4, 2013 by Marcus

Chemistry
Many portable gas heaters and grills use propane, C3H8(g). Using enthalpies of formation, calculate the quantity of heat produced when 17.0g of propane is completely combusted in air under standard conditions. Assume that liquid water is forming.
March 3, 2014 by Jessica

General chemistry
Many portable gas heaters and grills use propane, C3H8(g). Using enthalpies of formation, calculate the quantity of heat produced when 16.0g of propane is completely combusted in air under standard conditions. Assume that liquid water is forming.
October 16, 2013 by Victoria

Chemistry!
When 2.5g of NaOH were dissolved in 49.0g water in a calorimeter at 24.0 C, the temperature of the solution went up to 37.1 C. a. Is the solution reaction exothermic? Why? The temperature or the water went from 24.0 to 37.1 which is an increase. If the solution of NaOH in ...
December 4, 2006 by DrBob222

Chemistry
The standard free energy change, delta f G, for the formation of NO (g) from its elements is +86.58 kJ/mol at 25 degrees C. Calculate Kp at this temperature for the equilibrium 1/2 N2(g) + 1/2 O2(g) = NO(g) Comment on the sign of delta G and the magnitude of Kp.
April 30, 2014 by Sha

chem
please help me? :) topic: standard enthalpies of formation "Calculate ΔHf of octane, C8H18(l), given the entalpy of combustion of octane to CO2(g) and H2O(l) is -5471kJ/mol. The standard enthalpies of formation ofCO2 and H2O are given: CO2(g)ΔHf=-393.5kJ/mol and ...
April 16, 2011 by marie

Chemistry II
C4H4 (g) + 2 H2 (g) --> C4H8 (g) Combustion reactions involve reacting a substance with oxygen. When compounds containing carbon and hydrogen are combusted, carbon dioxide and water are the products. Using the enthalpies of combustion for C4H4 (-2341 kJ/mol), C4H8 (-2755 kJ...
May 20, 2007 by Jayd

Science
Many portable gas heaters and grills use propane, C3H8(g), as a fuel. Using standard enthalpies of formation, calculate the quantity of heat produced when 11.90 g of propane is completely combusted in air under standard conditions. I got -600 kj but its wrong
November 7, 2012 by Samantha

chemistry
For the reaction shown below complete the following calculations. H2(g) + C2H4(g) --> C2H6(g) (a) Estimate the enthalpy of reaction using the bond energy values in Table 9.4. (b) Calculate the enthalpy of reaction, using standard enthalpies of formation. (ΔHf for H2, ...
October 27, 2008 by hannah

chemistry
calculate the heat of combustion for the following reactions from the standard enthalpies of formation 2H2(g) + O2(g) = 2H2O(l) 2C2H2(g) + 502(g) = 4CO2(g) + 2 H2O(l)
October 21, 2011 by TROUBLED

chemistry
calculate the heat of combustion for the following reactions from the standard enthalpies of formation 2H2(g) + O2(g) = 2H2O(l) 2C2H2(g) + 502(g) = 4CO2(g) + 2 H2O(l)
October 21, 2011 by TROUBLED

Chemistry
Use standards entropies and heats of formation to calculate delta Gf at 25C for a. cadmium (II) chloride (s) b. methyl alcohol, CH3OH (l) c. copper (I) sulfide (s) I really have no idea where to start with this problem. I have no idea how to calculate delta Gf, and everything ...
November 9, 2013 by Olivia

Chemistry
Given 2Al2O3 (s) --> 4Al(s) + 3O2 (g) (standard enthalpy change= 3351.4 kJ) a) What is the heat of formation of aluminum oxide? How do I find heat of formation from standard enthalpy change? I know how to do it when I'm given enthalpy, but they aren't the same thing- ...
January 31, 2007 by Chris

Chemistry
Explain why the calculated value for the (1) enthalpy of combustion for propane using bond energies (bond breaking and bond formation)might not be in close agreement to the values calculated using (2) Hess Law and the values calculated using the (3) summation of the change in ...
November 1, 2010 by Leah

Chemistry
Use standard enthalpies of formation to calculate the heat produced by the combustion of one mole of ethanol by the following equation: C2H5OH (l) + 3 O2 (g) --> 2 CO2 (g) + 3 H2O (g).
November 2, 2011 by Anonymous

ap chem
The heat of combustion of propane is -2,220.1 kJ/mol calculate the heat of formation, delta Hf, of propane given that delta Hf of H20= -285.3 kJ/mol and delta Hf of CO2 = -393.5 kJ/mol
March 15, 2011 by Anonymous

chemistry
Calculate enthalpy change of reaction for the combustion of gaseous ethanol. C2H5OH + 3O2 >> CO2 + 3H2O. Using standard molar enthalpies of formation. C2H5OH -235.3 ( it's negative sign) CO2 -393.5 H2O -241.8 (1) Calculate the enthalpy change of reaction per mole of ...
April 20, 2010 by Alex

chemistry
Given handbook std enthalpies of formation at 298K for C5H10 (liq)=-105.9 kJ/mol and C5H10 (g)=-77.2 kJ/mol, estimate the normal boiling point of cyclopentane. I calculated delta H (vap or rxn) to be +28.7 kJ/mol. I am not sure how to proceed from here. Thank you very much for...
September 22, 2011 by Holly

Chemistry
Given the Data: N2(g) + O2g) = 2NO(g) delta H = 180.7kj, 2NO(g) + O2(g) = 2NO2(g) delta H = 0113.1kj, 2N2O(g) = 1N2(g) + O2(g) delta H = -163.2kj. Using Hesss Law calculate delta H for the reaction: N2O(g) + NO2(g) = 3NO(g)
July 3, 2014 by Brett

Chemistry
Given the Data: N2(g) + O2g) = 2NO(g) delta H = 180.7kj, 2NO(g) + O2(g) = 2NO2(g) delta H = 0113.1kj, 2N2O(g) = 1N2(g) + O2(g) delta H = -163.2kj. Using Hesss Law calculate delta H for the reaction: N2O(g) + NO2(g) = 3NO(g)
July 3, 2014 by Dan

Chem
(c) Using the appropriate Ksp value from Appendix D, calculate the solubility of Cu(OH)2 in grams per liter of solution. Appendix D: Ksp for Cu(OH)2 = 4.8 x 10-20 thanks!
April 27, 2011 by Rebekah

Chemistry
I am having trouble with this equation and calculating the enthalpy of formation. 2 NaHCO3 (s) --> Na2CO3 (s) + H2O (g) + CO2 (g) delta H129.2kj I get as far as this step and then I dont know what to do next. delta H= [1*delta H (Na2CO3) + 1* delta H(H2O (g)) + 1* delta H(...
April 30, 2013 by Laura

chemistry
If heat of reaction, Ca(s) + 2H+(aq) Ca2+(aq) + H2(g) , is - 544 kJ/mol, heat of reaction, CaO(s) + 2H+(aq) Ca2+(aq) + H2O(l) , is -192 kJ/mol. and heat of formation of water is -286, what is heat of CaO? Ca(s) etc is equation 1. CaO + 2H^+ etc is equation 2. H2 + 1/2 O2 ==>...
February 10, 2007 by nicholas

chemistry
ammonium nitrate decomposes to N2O and water at temperatures between 250 C and 300 C. Write a balanced chemical reaction describing the decomposition of ammonium nitrate, and calculate the standard heat of reaction using the appropriate enthalpies of formation. Please include ...
March 28, 2012 by Tori

chemistry
2. Methanol, CH3OH, is used as fuel in race cars. This liquid fuel can be synthesized using the following process C(s)+ O2(g) + 2H2(g)  CH3OH(l) Calculate delta G using the deta Gf of the reaction. Calculate Kp. What is the relation between the magnitude of delta G ...
April 15, 2010 by Kristen

CHEMISTRY
I know I posted this question before, but can you clarify it?? MY QUESTION IS AFTER YOU SWITCHED THE DELTA H1 THE CHANGE IN THE ENTHALPY IS NEGATIVE.... BUT THAT DOES NOT MAKE SENSE BECAUSE THE CHANGE IN ENTHALPY OF THE ORIGINAL DELTA H1 IS NEGATIVE(ACCORDING TO THE ...
November 14, 2013 by Anonymous

Chemistry
I know I posted this question before, but can you clarify it?? MY QUESTION IS AFTER YOU SWITCHED THE DELTA H1 THE CHANGE IN THE ENTHALPY IS NEGATIVE.... BUT THAT DOES NOT MAKE SENSE BECAUSE THE CHANGE IN ENTHALPY OF THE ORIGINAL DELTA H1 IS NEGATIVE(ACCORDING TO THE ...
November 14, 2013 by Anonymous

chemistry
Carbon disulfide is a colorless liquid. When pure, it is nearly odorless, but the commercial product smells vile. Carbon disulfide is used in the manufacture of rayon and cellophane. The liquid burns as follows. CS2(l) + 3 O2(g) → CO2(g) + 2 SO2(g) Calculate the standard...
October 29, 2010 by caroline

chemistry
A studen is asket to calculate the amount of heat involved in changing 10.0 g of liquid bomine at room temperature (22.5 C) to vapor at 59.0 C. To do this, one must know specific heat (0.474 J/g*C), boiling point (59 C), and heat of vaporization (29.6 kJ/mol) of bromine.In ...
March 30, 2011 by Lena

Chemistry
I need to calculate the value of Kp at 25 degrees celsius using the delta Go value. Delta Go = -29.10kJ I know that Delta Go = -RT lnK and that R=8.314e-3kJ/K mol -delta Go / RT I did -29.10 / 8.314e-3 X 298K and -11.74 but this was wrong. I am stuck. What did I do wrong?
April 23, 2012 by Hannah

Calculus-Solved - Incorrect
calculate delta y for f(x)= x^(3/2) with x= 4 and delta x= dx=0.1 delta y= f(x+delta x)- f(x) = f(4.1) - f(4) delta y= f(4.1)-8 f(x + delta x)= 8 + 3/2*x^(1/2)*0.1 = 8 + 0.15x^(1/2) = 8 + 0.30 = 8.30 delta y= 8.30 - 8 delta y= 0.30 but this is wrong. why is it wrong?
May 4, 2013 by Alaina

Chem
For the reaction I2(s)+Cl2(g) ==> 2ICl(g) delta H= 36kJ, delta S= 158.8J/K at 25 C. Calculate the temperature at which Keq is 4.0*10^3. delta G= (delta H)- T(delta S) = 36 - (298)(0.1588) = -11.32 delta G= -RTlnK -11.32= -8.31Tln(4*10^3) -11.32= -6892.35 T T= .00164 > ...
August 10, 2009 by ---

Chemistry(Please check answers)
1) The standard molar entropy value of N2 (g) is 191.5 J/K-mol, of O2 (g) is 205.0 J/K-mol and of NO2 (g) is 240.0 J/K-mol. From these values we can calculate the Delta So for the reaction N2 (g) + 2 O2 (g)-> 2 NO2 (g) to be? I did products - reactants (240 X 2) - [191.5...
April 23, 2012 by Hannah

chemistry
Combustion reactions involve reacting a substance with oxygen. When compounds containing carbon and hydrogen are combusted, carbon dioxide and water are the products. Using the enthalpies of combustion for C4H4 (-2341 kJ/mol), C4H8 (-2766 kJ/mol) and H2 (-286 kJ/mol), ...
December 28, 2010 by Lux

Chemistry for Eng.
Select the delta H values associated with the dissolution of lithium chloride that are exothermic. delta H1: energy associated with the separation of water molecules delta H2: energy associated with the separation of ions delta H3: energy associated with the formation of water...
November 1, 2012 by Anonymous

Chemistry
Can someone PLEASE help me with this???? I am soooo confused with this problem!!! Combustion reactions involve reacting When compounds containing carbon and hydrogen are combusted, carbon dioxide and water are the products. Using the enthalpies of combustion for C4H4 (-2341 ...
October 26, 2009 by Natalie

Chemistry
For the reaction described by the chemical equation: 3C2H2(g) -> C6H6(l) .. Delta H rxn = -633.1 kJ/mol a) Calculate the value of Delta S rxn at 25.0 C... b) Calculate Delta G rxn... c) In which direction is the reaction, as written, spontaneous at 25 C and 1 bar pressure...
March 9, 2012 by Katherine

chemistry
A scientist measures the standard enthalpy change for the following reaction to be -2923.0 kJ : 2C2H6(g) + 7 O2(g) 4CO2(g) + 6 H2O(g) Based on this value and the standard enthalpies of formation for the other substances, the standard enthalpy of formation of CO2(g) is _________
October 24, 2012 by Anonymous

Chemistry(Please help)
1) Nitrosyl chloride (NOCl) decomposes at high temperature. The equation is 2 NOCl (g) -> 2 NO (g) + Cl2 (g) at 227oC Using delta Ho = 81.2 kJ and delta So = 128 J/K, calculate the value of the equilibrium constant for this reaction. I do not know how to start this problem...
April 24, 2012 by Hannah

Physical Chemistry
Calculate the equilibrium constant at 25C and at 100.C for each of the following reactions, using data available in Appendix 2A. Remember that the organic molecules are in a separate section behind the organic molecules in Appendix 2A. (a) HgO(s) Hg(l) + O2(g) at 25C Found ...
February 19, 2010 by Trixie

Chemistry
Use standard heats of formation in Appendix L to calculate standard enthalpy changes for the following reactions. 1.45 x 10-2 mol of carbon is oxidized to CO2(g) Please help me!
May 1, 2011 by Kat

AP CHEMISTRY
Using the tables of enthalpies of formation and entropies of formation, estimate the boiling point for the following liquid: methanol (CH3OH), ethanol (C2H5OH) and acetic acid (CH3COOH). compare to their tabled boiling points. how would i go about working this question? table ...
October 7, 2007 by John

Chemistry
I have some enthalpies of formation for a reactant and transition state but calculated using different computational methods. I want to find the ratio of the forward rate constants determined using both methods but I'm not really sure how. I thought I could maybe use ...
March 13, 2010 by Alice

CHEMISTRY- urgent
Using the tables of enthalpies of formation and entropies of formation, estimate the boiling point for the following liquid: methanol (CH3OH), ethanol (C2H5OH) and acetic acid (CH3COOH). compare to their tabled boiling points. how would i go about working this question? table ...
October 7, 2007 by John

Mike
N2 + 3H2 --> 2NH3 At 25°C (delta)Ho = -92.22 kJ and (delta)So = -198.53 J/K. Using this information, calculate the equilibrium constant for the reaction at 2.43x10^2°C. (R = 8.314 J/K) Apparently the way I'm doing it is wrong: I divide 198.53 by 1000 then multiply by 298 ...
November 17, 2007 by Chemistry

Dan
N2 + 3H2 --> 2NH3 At 25°C (delta)Ho = -92.22 kJ and (delta)So = -198.53 J/K. Using this information, calculate the equilibrium constant for the reaction at 2.43x10^2°C. (R = 8.314 J/K) Apparently the way I'm doing it is wrong: I divide 198.53 by 1000 then multiply by 298 ...
November 17, 2007 by Chem

chemistry
Calculate the value of T delta S (KJ) of reaction for the equation as written. (It is given that the standard enthalpies (J/K mol)are CH3COOH=159.8, O2=205.138, CO2=213.7, H20=69.91) CH3COOH(l) + 2 O2(g) --> 2 CO2(g) + 2H2O(l)
March 9, 2008 by Anonymous

chemistry
consider the following reaction: C3H8 (g)+ 5O2 (g)--> 3CO2 (g)+ 4H20 (g) Delta H = -2440kJ The heat of formation of CO2 is -390 kJ/mol and the heat of formation of H2O is -240 kJ/mol. What is the heat of formation of propane?
January 13, 2011 by madison

Chemistry
delta G reaction = delta G products - delta G reactants. Hydrogen peroxide is used as a bleachin agent, a disinfectant and medicinally as a topical antibacterial agent. Hydrogen peroxide decomposes according to the reacton 2H^2O^2(l)-->2H^2O(l)+o^2(g) A. Given the standard ...
May 15, 2007 by DrBob222

Chemistry
CONTINUE>>>>>>>>>>> The enthalpy changes for two different hydrogenation reactions of C2H2 are: C2H2+H2---->C2H4 Delta H 1 (there is a degree sign....standard enthalpy of formation??) *****WAIT A SECOND, IF I USE THE HEAT OF FORMATION ...
November 14, 2013 by Anonymous

Chem
RXN #1: H2 (g) + O2 (g) --> H2O2 (l) ; delta-H =? Calculate the enthalpy change (delta-H1) for the reaction above (RXN #1) using the information below and Hess' Law. RXN A: H2O2 (l) --> H2O (l) + 1/2 O2 (g); delta-H=-98.0 kJ/mol RXN B: 2 H2 (g) + O2 --> 2 H2O (l); ...
July 12, 2011 by Ally

chemistry
A scientist measures the standard enthalpy change for the following reaction to be -53.4 kJ : Ca(OH)2(aq) + 2 HCl(aq) CaCl2(s) + 2 H2O(l) Based on this value and the standard enthalpies of formation for the other substances, the standard enthalpy of formation of H2O(l) is kJ/mol
March 18, 2012 by Austin

chemistry
A scientist measures the standard enthalpy change for the following reaction to be -53.4 kJ : Ca(OH)2(aq) + 2 HCl(aq) CaCl2(s) + 2 H2O(l) Based on this value and the standard enthalpies of formation for the other substances, the standard enthalpy of formation of H2O(l) is kJ/mol
March 18, 2012 by Austin

Chemistry
Standard enthapies of formation are not always like bond enthalpies.Explain
July 12, 2011 by Gift

chemistry
Use the thermochemical equations: 1/2 H2(g)+1/2 I2(g) ...............> HI(g) delta H = -1.1 k cal 1/2 H2(g).......> H2 (g) delta H = -104.2 k cal 1/2 I2 (g)..............> I (g) delta H = +18.1 k cal To present for the formation of hydrogen iodide gas from gaseous ...
November 16, 2010 by miss

Chemistry
Calculate the delta H and delta S for the reaction. From there, calculate the delta G at 25 degrees Celsius. Predict whether it the reaction is spontaneous or non-spontaneous under standard conditions. CH3OH(l)+ O2(g)--> HCO2H(l)+ H2O(l) *i could not find the find the delta...
February 26, 2010 by Anonymous

Chemistry
Calculate the DELTA H(rxn), DELTA S(rxn), DELTA S(universe), DELTA G(rxn). For each system below indicate whether DELTA S and DELTA H are positive or negative. Then indicate if the reaction is entropy driven, enthalpy driven or neither. C3H8(g) + 2O2(g) => 3CO2(g) + 4H2O(g)
September 19, 2008 by Zach

Chemistry
Using the following data calculate Delta Sfus and Delta Svap for K in J/mol-k Tm(K) = 336, Delta H Fus(kJ/mol) = 2.33, Tb (K) = 1033, Delta H vap (kJ/mol) = 77.1 For Delta S fus i'm supposed to use 336 K the Tm value and for Delta S vap i'm supposed to use 1033 K the Tb value ...
March 9, 2012 by Katherine

Chem
Does my work here look right? 3. One mole of an ideal gas expands adiabatically into a vacuum. Calculate q, delta-e, w, and delta-H for the process. q= 0 [adiabatic] w= -Pext(V2-V1) w= 0 delta-e = w + q delta-e = 0 + 0 = 0 delta-h= delta-e + P(delta V) delta-h= 0 + 0 = 0 does ...
February 3, 2007 by Jess

Chemistry II
The value of ^G for the following reaction is -5490 kJ. Use this value and data to calculate the standard free energy of formation for C4H10 (g). 2 C4H10 (g) + 13 O2 (g) --> 8 CO2 (g) + 10 H2o (l) Do you know the heats of formation for CO2 and H2O? Wouldn't delta G/2, minus...
May 23, 2007 by Jayd

chemistry
CH4 + 2O2 ---> CO2 + 2H2O Delta H H2O= -285.8 kJ/mole Delta H CO2= -393.3 kJ/mole What is the standard heat of formation of methane, Delta H CH4, as calculated from the data above
November 18, 2011 by kc

CHEMISTRY
calculate the delta h for the reaction 2C+2H--> C2H4 C+O2--> Co2 delta h= -393.5 C2H4+ 3O2--> 2CO2+ 2H2O delta h= 1410.9 H2+ 1/2 O2--> H2O delta h= -285.8 2CO+ O2--> 2CO2 delta h= -566.0 do you flip the first two equations and times the first and third one by 2?
June 6, 2010 by Anonymous

Chemistry
Please explain. The enthalpy changes for two different hydrogenation reactions of C2H2 are: C2H2+H2---->C2H4 Delta H 1 C2H2+2H2---->C2H6 Delta H 2 Which expression represents the enthalpy change for the reaction below? C2H4+H2---->C2H6 Delta H = ? A. Delta H 1 + ...
November 11, 2013 by Anonymous

CHEMISTRY
Please explain. The enthalpy changes for two different hydrogenation reactions of C2H2 are: C2H2+H2---->C2H4 Delta H 1 C2H2+2H2---->C2H6 Delta H 2 Which expression represents the enthalpy change for the reaction below? C2H4+H2---->C2H6 Delta H = ? A. Delta H 1 + Delta...
November 11, 2013 by Anonymous

Chemistry(Please check answers)
1) For a reaction delta Go is more negative than delta Ho. What does this mean? a. delta So is zero. b. delta So is negative c. delta So is positive d. delta So is negative if delta Ho is positive. e. delta So is negative if delta Ho is negative. I think that delta S is ...
April 23, 2012 by Hannah

Chemistry Urgent
Assuming that kerosene is C11H24, calculate the standard enthalpy change when 1 mole of kerosene burns completely in oxygen, using the data below: ΔH of formation of C11H24(l) = -327 kJ mol ΔH of formation of CO2(g)= -394 kJ mol ΔH of formation of H2O (l)= -286 ...
March 9, 2014 by Ava

chemistry
Calculate te calue of Ksp for Ca(NO3)2 using the data below. Ba(aq) delta G0f= -561 kJ/mol NO3 (aq) delta G0f= -109 kJ/mol BaNO3 (s) delta G0f= -797 kJ/mol
November 27, 2010 by Jeffery

chem
calculate the delta Hf of c6h12o6 (s) from the following data: Delta H combustion= -2816 kj/mol delta Hf of Co2 = -393.5 kj/mol delta Hf= of H2 O= -285.9kj/mol
March 4, 2012 by Cece

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