Friday
April 18, 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: 57,666

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...
Monday, July 18, 2011 at 8:19pm by priya

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.
Tuesday, April 30, 2013 at 10:02am 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?
Sunday, May 8, 2011 at 2:53pm by Betsie

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
Tuesday, October 25, 2011 at 9:21pm 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
Tuesday, October 25, 2011 at 9:21pm by jen

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
Monday, March 4, 2013 at 11:08am 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 ...
Monday, April 13, 2009 at 11:59am by Brigette

Chemistry-Enthalpies of formation
Look up the delta Hf in your text or notes, then delta Hrxn = (delta H products)-(delta H reactants). H2 will be zero. Therefore, it is DHrxn = (4*DHof CO)-(3*DHCH4+2*DHH2O+DHCO2)
Monday, April 13, 2009 at 11:59am by DrBob222

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 ...
Saturday, April 3, 2010 at 11:58pm by Anna

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
Saturday, December 4, 2010 at 5:31pm by Ashley

Chemistry
Calculate the enthalpy of combustion for acetic acid using standard enthalpies of formation.
Monday, November 12, 2012 at 8:19pm by Diana

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 ...
Thursday, January 30, 2014 at 7:40am by BOB

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.
Friday, October 14, 2011 at 9:05pm by John

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
Wednesday, July 4, 2012 at 7:25am by mala

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 (...
Sunday, October 31, 2010 at 9:54pm 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 (...
Monday, November 1, 2010 at 10:19pm by Willy

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.)
Sunday, April 6, 2014 at 10:29pm by Anonymous

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 ...
Saturday, November 17, 2012 at 6:38pm by DeeDee

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(...
Monday, January 23, 2012 at 9:47pm by timmy

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
Sunday, November 6, 2011 at 3:26pm by Kay

chemistry
Consider the reaction 3CH4(g)= C3H8(g)+ 2H2(g). Using data from Appendix C in the textbook, calculate delta G at 298 K.
Tuesday, February 14, 2012 at 6:47pm by Anonymous

Chemistry
Or calculate dHo and dSo at standard enthalpies of formation and entropies?
Thursday, March 27, 2014 at 1:31am by Airin

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...
Saturday, January 21, 2012 at 7:16pm by Hannah

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
Thursday, April 8, 2010 at 3:26pm by Anonymous

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.
Thursday, March 25, 2010 at 9:37pm by hello

chemistry
Calculate the experimental heat of reaction using qwater = - qreaction. (use the mass of the solution at maximum temperature to be equal to the mass of the water). (57.97C=-57.97C) Calculate the theoretical heat of reaction. Steps.. 1. Write a balanced equation, including the ...
Monday, June 29, 2009 at 7:43pm by Gweedo8

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
Thursday, February 27, 2014 at 6:27pm by Steve

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...
Thursday, November 4, 2010 at 1:30am by Jarrod

Thermodynamics
The molar enthalpy of formation of water vapor is -241.82 kJ/mol at 298 K. Calculate the molar enthalpies of formation of water vapor and of liquid water at 100 C and at -0.1 C (four values).
Wednesday, October 3, 2007 at 10:27am by kristina

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.
Friday, October 4, 2013 at 8:58pm 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.
Monday, March 3, 2014 at 4:38pm by Jessica

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 ...
Sunday, July 25, 2010 at 10:36pm by rick

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...
Sunday, February 17, 2008 at 4:27pm by Lauren

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?
Wednesday, October 24, 2007 at 10:04pm by Jake

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.
Wednesday, October 16, 2013 at 9:06pm by Victoria

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 ...
Tuesday, February 14, 2012 at 7:31pm by Anonymous

chemistry
OK. I didn't read the problem correctly. You look up in tables for delta H formation and delta Hrxn = (delta H products)-(delta H reactants). Solve for delta H of the amine.
Monday, June 21, 2010 at 11:18am by DrBob222

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
Wednesday, November 7, 2012 at 4:39pm by Samantha

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)
Friday, October 21, 2011 at 10:37pm 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)
Friday, October 21, 2011 at 10:37pm by TROUBLED

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 ...
Monday, November 1, 2010 at 11:40am by Leah

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, ...
Monday, October 27, 2008 at 11:24pm by hannah

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 ...
Saturday, April 16, 2011 at 8:09pm by marie

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 ...
Tuesday, April 20, 2010 at 10:00am by Alex

chemistry
delta H rxn = delta H products - delta H reactants. Look up delta H formation in your text or on line.
Sunday, October 19, 2008 at 10:26pm by DrBob222

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).
Wednesday, November 2, 2011 at 11:14pm by Anonymous

Physical Chemistry
I figured out what I was doing...I ended up using the Van't Hoff Equation and the enthalpies of formation to solve for K at 100 C. This stuff is so time consuming...
Friday, February 19, 2010 at 9:29pm by Trixie

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 ...
Wednesday, March 28, 2012 at 4:30pm by Tori

Chemistry
The second equation gives the delta H for the REACTION as it is written from reactants producing products. The numbers one uses comes from tables which have been prepared from experimentally measured HEATS OF FORMATION (or calculated from different heats of formation using ...
Monday, April 5, 2010 at 11:09pm by DrBob222

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 ...
Friday, January 20, 2012 at 9:55pm by Hannah

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-...
Sunday, March 4, 2007 at 4:03pm by Chris

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...
Friday, October 29, 2010 at 12:53am by caroline

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...
Sunday, May 20, 2007 at 6:52pm by Jayd

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 ...
Saturday, November 9, 2013 at 7:41pm by Olivia

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!
Wednesday, April 27, 2011 at 5:53pm by Rebekah

Chem
oops... (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
Wednesday, April 27, 2011 at 5:26pm by Rebekah

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 ...
Monday, December 4, 2006 at 1:30am by DrBob222

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...
Tuesday, February 14, 2012 at 10:16am by Hannah

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- ...
Wednesday, January 31, 2007 at 8:40pm by Chris

chem 101
2C2H6O + 6O2 ==> 4CO2 + 6H2O heat comb = (n*dHf CO2 + n*dHf H2O) - (2*dHf ethanol) = ? dHf = heat formation = delta Hf. These are in the appendix in your text/notes.
Wednesday, April 11, 2012 at 3:37pm by DrBob222

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 ...
Thursday, April 15, 2010 at 7:32am by Kristen

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...
Thursday, September 22, 2011 at 4:25pm by Holly

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(...
Tuesday, April 30, 2013 at 9:27pm by Laura

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 ...
Saturday, March 13, 2010 at 6:33am by Alice

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 _________
Wednesday, October 24, 2012 at 12:42am by Anonymous

Chemistry
Look up heat formation SnO2 and SnO. delta Hrxn = (DHproducts)-(DHreactants). [Note: heat formation O2 is zero). Delta Hrxn will be for 2 moles SnO2. Find the proportion of 85.0 grams.
Monday, May 31, 2010 at 10:35pm by DrBob222

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!
Sunday, May 1, 2011 at 5:10pm 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 ...
Sunday, October 7, 2007 at 1:07pm by John

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 ...
Sunday, October 7, 2007 at 5:48pm by John

Chemistry
Standard enthapies of formation are not always like bond enthalpies.Explain
Tuesday, July 12, 2011 at 3:22am by Gift

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
Tuesday, March 15, 2011 at 12:09am by Anonymous

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), ...
Tuesday, December 28, 2010 at 1:34pm by Lux

chemical equilibrium
Look up and calculate delta Go formation for the reaction at 25 C. Then dGof = -RTlnK. Solve for K.
Monday, July 9, 2012 at 1:10pm by DrBob222

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 ...
Monday, October 26, 2009 at 12:41am by Natalie

chemistry
The first delta G is for a general reaction at the specified conditions. The delta Go is a "standard delta G as 25 C" when using delta Hformation at 25 and delta Sformation at 25C. (I assume knot means naught). Delta G is the one to use for spontaneity but remember delta G is ...
Sunday, October 17, 2010 at 5:50pm by DrBob222

chemistry
Look in your problem. There must be a temperature given if you are to calculate TdeltaS. delta S is calculated by delta S reaction = (sum of delta S products ) - (sum of delta S reactants). Then T*delta S is just T times that.
Sunday, March 9, 2008 at 11:07pm by DrBob222

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...
Thursday, November 1, 2012 at 12:48am by Anonymous

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 ...
Friday, February 19, 2010 at 9:29pm by Trixie

chemistry
delta T = Kb*molality molality = moles/kg solvent moles = g/molar mass [convert 22.8 g glucose to moles using equation 3. Convert moles glucose to molality using equation 2. Then calculate delta T using equation 1.] Then delta T = Kf*m for the freezing point section. The same ...
Sunday, February 28, 2010 at 1:25pm by DrBob222

chemistry
q = massmetal x Cpmetal x delta Tmetal. q = massH2O x CpH2O x delta TH2O. Use equation 2 first to calculate q, then use equation 1 (using q from the first calculation) to calculate Cp metal. Post your work if you get stuck.
Friday, February 8, 2008 at 7:55pm by DrBob222

chemistry
By using the bond enthalpies and bond energies in thermochemical equations to calculate the reaction enthalpy of; H + Br=2HBr
Sunday, July 10, 2011 at 3:29am by Gift

Chemistry
Calculate the enthalpy of combustion of acetylene(per mol acetylene)using bond enthalpies and energy diagram
Friday, August 5, 2011 at 2:15pm by Gift

Chemistry
Calculate the enthalpy of combustion of acetylene(per mol acetylene) using bond enthalpies and energy diagram
Friday, August 5, 2011 at 6:20pm by Gift

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?
Saturday, May 4, 2013 at 6:58pm by Alaina

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...
Wednesday, May 23, 2007 at 7:21am by Jayd

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...
Friday, February 26, 2010 at 6:53pm by Anonymous

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 ...
Wednesday, March 30, 2011 at 8:52pm by Lena

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?
Thursday, January 13, 2011 at 9:06pm by madison

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...
Tuesday, April 24, 2012 at 11:35am by Hannah

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
Sunday, March 18, 2012 at 6:24pm 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
Sunday, March 18, 2012 at 6:24pm by Austin

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)
Sunday, March 9, 2008 at 11:07pm by Anonymous

Chem
H is 2.1. B is 2.0. Almost the same. I would write a delta delta (two small delta) + for B and a delta delta - for H. The delta delta + or - signifies an extremely small negative or positive charge. You can carry this when explaining to delta delta delta - and +.
Wednesday, July 8, 2009 at 9:07pm by DrBob222

Thermochemistry
Hint: Write the balanced combustion reaction. You can find the standard enthalpies of formation for O2, CO2, and H2O from many sources, including the CRC Handbook of Chemistry and Physics. Solution: Balanced combustion reaction: C8H18 + 12.5 O2 --> 8 CO2 + 9 H2O From the ...
Sunday, December 4, 2011 at 8:58pm by Katie

Chemistry for Eng.
delta H3: energy associated with the formation of water-ion interactions delta Hsoln: the enthalpy of solution
Thursday, November 1, 2012 at 12:48am by michelle

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 ...
Sunday, March 9, 2014 at 10:17pm by Ava

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 ...
Thursday, November 14, 2013 at 6:43pm 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 ...
Thursday, November 14, 2013 at 7:32pm by Anonymous

Chemistry
Im sorry it so confusing and there is alot of data. This whole experiment was split into two parts. I had to work in a group with two other people to do part 2 and for part 1 we had to get the data from another group so I just have some of their data. For part I guess the ...
Monday, February 13, 2012 at 3:50pm by Hannah

Chemistry
Using data from Appendix C in the textbook, calculate the equilibrium pressure of CO2 at 1000K .
Sunday, March 31, 2013 at 6:55pm by Jonah

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