Lets number the reaction as 0, 1, 2, 3, 4 from top to bottom
required reaction should be written in terms of other reaction
This is Hess Law
required reaction can be written as:
reaction 0 = -1 * (reaction 1) +1 * (reaction 2) -2 * (reaction 3) +2 * (reaction 4)
So, ΔHo rxn for required reaction will be:
ΔHo rxn = -1 * ΔHo rxn(reaction 1) +1 * ΔHo rxn(reaction 2) -2 * ΔHo rxn(reaction 3) +2 * ΔHo rxn(reaction 4)
= -1 * (-910.9) +1 * (-1651.0) -2 * (-542.0) +2 * (-241.8)
= -139.7 KJ
Answer: -139.7 KJ
Hess's Law Practice Find AH° for the following equation: SiO2(s) + 4HF(g) → SiF4(g) + 2H2O(g)...
Calculate delta H rxn for each of the following: (a) SiO2(s) + 4HF(g) > SiF4(g) + 2H2O(l) (b) C2H6(g) + O2(g) > CO2(g) + H2O(g) [unbalanced] 6.54 Calculate AHºrxn for each of the following: (a) SiO2(s) + 4HF(g) → SiF4(g) + 2H20(1) (b) CH6(g) + O2(g) → CO2(g) + H2O(g) [unbalanced]
Consider the following: SiF4 (g) + 2H2O (g) < ---> SiO2 (s) + 4HF (g) Kp=7.44 x 10-3 at 2000 K a) Write the equilibrium expression b) Calculate Kc for the above reaction. Will the reaction go to the right, the left, or is it at equilibrium under the following initial conditions? [HF] = 0.100M Given the above information, calculate the value of Kp for the following reaction at 2000 K: 1/2 SiO2 (s) + 2HF (g) <- ->...
2. Use Hess’s Law to determine the enthalpy of the reaction below. 2F2(g) + 2H2O(l) → 4HF(aq) + O2(g) DH˚= ? H2(g) + F2(g) → 2HF(aq) DH˚ = -546.6 kJ 2H2 (g) + O2(g) → 2H2O(l) DH˚ = -571.6 kJ a. 42 kJ b. -1120 kJ c. -251 kJ d. -521 kJ e. -1690 kJ
18. Given that AHorxn = -546.6 kJ H2 (g)+F2 (g)2HF (g) AH°rxn = -571.6 kJ 2H2 (g)+ O2 (g) 2H20 (1) Calculate the value of AHrxn for 2F2 (g) 4HF (g) + O2 (g) +2H20 (I)
Calculate AH for the reaction CyHa(s) + 6F2(8) 2CF4(8) + 4HF(G) given the following information: As part of your answer, show how the equations can be added together to give the overall or net equation H2(g) + F2(g) + 2HF(g) AH--537 kJ C(s) + 2F2(8) CF4(8) AH--680. kJ 2C(s) + 2H2(g) → C2H4(8) AH- +52.3kJ HTML Editore BIVA-A- IEE311xx, - E V O 1 12pt - Paragraph -
A chemist knows that the kJ for the reaction 2H2(g) + O2 (g) ---> 2H2O (g) ,and that kJ for the reaction H2 (g) + F2 (g) ---> 2HF (g). With this information he calculated the for the reaction 2H2O (g) + 2F2 (g) ---> 4HF(g) + O2 (g) and predicted whether was positive or negative. How? A Ho- 485
Practice with Hess's Law and Standard Heats of Formation 1. (Example) The reaction C2H4 (g) + 6 F2 (g) → 2 CF4(g) + 4 HF (g) can be written as the sum of: C2H4 (9) ► 2 C(s) + 2 H2 (g) AH = -52.3 kJ/mol 2 C(s) + 4 F2 (9) ► 2 CF4(9) AH = -1360 kJ/mol 2 H2(g) + 2 F2 (g) → 4 HF (a) AH = -1074 kJ/mol C2H4(g) + 6 F2(g) → 2 CF4(g)...
Determine which of the following chemical equations are correctly balanced. Fe2O3(s)+CO(g)→2Fe(s)+CO2(g) Al2S3(s)+H2O(l)→2Al(OH)3(s)+3H2S(g) 2Cr(s)+3O2(g)→Cr2O3(s) SiO2(s)+4HF(aq)→SiF4(g)+2H2O(l)
Practice with Hess's Law and Standard Heats of Formation 1. (Example) The reaction C He(g) + 6 F2 (g) → 2 CF4(g) + 4 HF (9) can be written as the sum of: CH4 (9) ► 2 C(s) + 2 Ha(o) AH = -52.3 kJ/mol 2 C(s) + 4 Faq) → 2 CF4g) SH -1380 kJ/mol 2 Haq) + 2 Fala) > 4 HF HE.1074 kJimol CsHe(g) + 6 F2 (g) → 2 CF.(g) + 4 HF (g) AH =...
Ch. 5, 6 A What is AH rxn for the following reaction? SIO2 (s) + 4HCl(g) → SiCl4(g) + 2H20(9) Substance AH {(kJ/mol) SIO2(5) 859.3 SiCl4(9) 662.8 HCl(9) -92.3 H20(9) -241.8 Multiple Choice о -1856.2 kJ/mol о -13726 kJ/mol О -470 kJ/mol