Chem

Change in enthalpy problem. Consider the reaction represented below. Referring to the data in the table below, calculate the standard enthalpy change for the reaction at 25 degrees C.

O3(g)+NO(g)-->O2(g)+NO2(g)

Standard enthalpy of formation in kJ/mol:

O3(g) 143
NO(g) 90
NO2(g) 33

I am sure this isn't a hard problem, but I can't really remember how to do it.

  1. 👍
  2. 👎
  3. 👁
  1. delta Hreaction = delta Hproducts - delta Hreactants

    1. 👍
    2. 👎
  2. Ok, so I have DeltaHrxn=(X+90)-(143+90). How do you calculate the enthalpy of O2 (X above) when it is not given to you. Am I even doing that right?

    1. 👍
    2. 👎
  3. No. Re-read my answer. I said
    PRODUCTS - REACTANTS.
    You have one of the reactants on the product side.
    DHrxn = DH products - DH reactants.
    DHrxn = (O2 + NO2) - (O3 + NO)
    DHrxn = (0 + 33) - (143 + 90) = ??

    1. 👍
    2. 👎
  4. drbob222 is correct . the answer is 200. DUh!!

    1. 👍
    2. 👎
  5. It's -200. not 200

    1. 👍
    2. 👎

Respond to this Question

First Name

Your Response

Similar Questions

  1. chemistry

    2C2H2(g) + 5O2(g)→4CO2(g) + 2H2O(g) a. Determine the enthalpy change for the reaction. ΔH = (4(-393.5)+ 2(-241.8)) – (2(227) + 5(0)) The enthalpy change is -2511.6. b. Determine the entropy change for the reaction. ΔS =

  2. Chemistry

    You wish to know the enthalpy change for the formation of liquid PCl3 from the elements shown below. P4(s) + 6 Cl2(g)--> 4 PCl3(l) ΔH°f = ? The enthalpy change for the formation of PCl5 from the elements can be determined

  3. Chemistry

    Are my answers correct? C6H14 + 19/2 O2 -> 6 CO2 + 7H2O enthalpy change = -4163 kJ a) if 0.537 mol of carbon dioxide is produced in the reaction represented by the equation above, how much heat is released by the reaction?

  4. Chemistry

    What is the enthalpy change for the first reaction? Fe2O3(s) → 2Fe(s) + 3/2O2(g) ΔH = 4Fe(s) + 3O2(g) → 2Fe2O3 (s) ΔH = -1,652 kJ I think I'm supposed to rearrange the equation and double everything but enthalpy isn't my

  1. 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

  2. Science

    The enthalpy change for the reaction 2 H2 + O2 > 2 H20 is -571.6 kJ. Determine the enthalpy change for the decomposition of 24.0g H2O. My Process -571.6 is the enthalpy of 2 mols of H2O. So the enthalpy of 1 mol of H2O will be

  3. AP Chem

    Reaction 1: NaOH + HCL --> H20 + NaCl delta H of -100.332 kj/mol Reaction 2: NaOH + NH4Cl --> NH3 + H20 : delta H of 358.639 kj/mol Reaction 3: HCl + NH3 --> NH4Cl : delta H of -51.701 kj/mol Use your answers from question 2 above

  4. Chem

    For the reaction, 3C2H2(g) ===> C6H6 at 25°C, the standard enthalpy change is -631 kJ and the standard entropy change is -430 J/K, Calculate the standard free energy change (in kJ) at 25°C. What is the formula that relates

  1. Chemistry

    Calculate the enthalpy change for the reaction: Zn (s) + S (s) + 2 O2 (g) → ZnSO4 (s) ΔH = ? kJ by using the following data: Zn (s) + S (s) → ZnS (s) ΔH = –206.0 kJ ZnS (s) + 2 O2 (g) → ZnSO4 (s) ΔH = –776.8 kJ My

  2. chemistry

    NH4NO3(s) NH4+(aq) + NO3−(aq) In order to measure the enthalpy change for this reaction above, 1.07 g of NH4NO3 is dissolved in enough water to make 25.0 mL of solution. The initial temperature is 25.8°C and the final

  3. Chemistry

    2 H2S (g) + SO2 (g) ƒnƒn3 S (s) + 2 H2O (g) 1) At 298 K, the standard enthalpy change, H¢X, for the reaction represented below is -145 kilojoules. (a) Predict the sign of the standard entropy change, S¢X, for the reaction.

  4. chemistry

    The reaction of iron with oxygen is very familiar. You can see the resulting rust on buildings, vehicles and bridges. You may be surprised, however at the large amount of heat that is produced by this reaction. 4Fe(g) + 3O2(g) 

You can view more similar questions or ask a new question.