Question

The enthalpy of combustion (ΔH°c) of cis-1-ethyl-4-methylcyclohexane (C9H18) is -5875.10 kJ/mol. Using the appropriate information given...

The enthalpy of combustion (ΔH°c) of cis-1-ethyl-4-methylcyclohexane (C9H18) is -5875.10 kJ/mol. Using the appropriate information given below, calculate the enthalpy of formation (ΔH°f), in kJ/mol, for cis-1-ethyl-4-methylcyclohexane.

Report your answer to two decimal places.



ΔH°f (CO2 (g)) = -393.51 kJ/mol

ΔH°f (H2O (l)) = -285.83 kJ/mol

Homework Answers

Answer #1

The required reaction is 9C(s) + 9H2 (g)-------> C9H18(g),   ^Hf =?? Now, from the given information the reactions can be written as:-   C9H18(g) + 27/2 O2(g) -----> 9 CO2( g) + 9H2O(g), ^Hc = -5875.10KJ/ mole. H2(g) + 1/2 O2(g)------> H2O(g), ^ Hf= -285.3 KJ/ mole. C(s) + O2(g) --------> CO2(g), ^Hf= -393.5KJ/ mole.      multiplying equation -3 by 9 and eqn-2 by 9 and then adding the two eqn,we get.    9C(s)+ 9H2 (g)+27/2 O2(g) -----> 9CO2(g) +9H2O(g), ^Hf= -6114.06KJ/mole ---eqn-4.    Now,by subtracting eqn-1 from eqn-4,we get. 9C(s)+ 9H2(g) -----> C9H18(g), ^ Hf= -238.96KJ/ mole

         r

Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
The standard enthalpy change of combustion [to CO2(g) and H2O(l)] at 25°C of the organic solid...
The standard enthalpy change of combustion [to CO2(g) and H2O(l)] at 25°C of the organic solid diphenyl phthalate, C20H14O4(s), is determined to be -9364.7 kJ mol-1. What is the Hf° of C20H14O4(s) based on this value?    Use the following data: Hf° H2O (l) = -285.83 kJ mol-1 ;   Hf° CO2(g) = -393.51 kJ mol-1 __________ kJ mol-1
1.Using the enthalpies of formation given below, calculate ΔH°rxn in kJ, for the following reaction. Report...
1.Using the enthalpies of formation given below, calculate ΔH°rxn in kJ, for the following reaction. Report your answer to two decimal places in standard notation. H2S(g) + 2O2(g) → SO3(g) + H2O(l) H2S (g): -20.60 kJ/mol O2 (g): 0.00 kJ/mol SO3 (g): -395.77 kJ/mol H2O (l): -285.83 kJ/mol 2. Calculate the amount of heat absorbed/released (in kJ) when 22.54 grams of SO3 are produced via the above reaction. Report your answer to two decimal places, and use appropriate signs to...
The standard enthalpy change of combustion [to CO2(g) and H2O()] at 25°C of the organic solid...
The standard enthalpy change of combustion [to CO2(g) and H2O()] at 25°C of the organic solid phthalic acid, C8H6O4(s), is determined to be -3207.3 kJ mol-1. What is the Hf° of C8H6O4(s) based on this value? Use the following data: Hf° H2O () = -285.83 kJ mol-1 ; Hf° CO2(g) = -393.51 kJ mol-1 kJ mol-1
9. Use the following experimentally derived combustion data to calculate the standard molar enthalpy of formation...
9. Use the following experimentally derived combustion data to calculate the standard molar enthalpy of formation (ΔH°f ) of liquid methanol (CH3OH) from its elements. 2 CH3OH(l) + 3 O2(g) → 2 CO2(g) + 4 H2O(l)     ΔH°rxn = −1452.8 kJ C(graphite) + O2(g) → CO2(g)                               ΔH°rxn = −393.5 kJ 2 H2(g) + O2(g) → 2 H2O(l)                                     ΔH°rxn = −571.6 kJ (1) −238.7 kJ/mol    (2) 487.7 kJ/mol       (3) −548.3 kJ/mol    (4) 20.1 kJ/mol         (5) 47.1 kJ/mol
Find ΔH° for the formation of solid vanillin, C8H8O3(s), using the data below. C(s) + O2(g)...
Find ΔH° for the formation of solid vanillin, C8H8O3(s), using the data below. C(s) + O2(g) → CO2(g) ΔH°= -393.52 kJ/mol H2(g) + ½O2(g) → H2O(l) ΔH°= -285.83 kJ/mol C8H8O3(s) + 8½O2(g) → 8CO2(g) + 4H2O(l) ΔH°= -3827.88 kJ/mol The heat of formation of solid vanillin is _______Kj mol-1
The standard enthalpy of formation of benzoic acid, C6H5COOH, is −385kJ mol−1 at 298 K. Calculate...
The standard enthalpy of formation of benzoic acid, C6H5COOH, is −385kJ mol−1 at 298 K. Calculate the standard enthalpy of combustion of benzoic acid at this temperature, given that the standard enthalpy of formation of liquid water, H2O is −285.8 kJ mol−1 and gaseous carbon dioxide, CO2, is −393.51 kJ mol−1. A −294.3 kJ mol−1 B −3997kJ mol−1 C −3227.0 kJ mol−1 D 2282.2 kJ mol−1
The standard heat of formation, ΔH∘f, is defined as the enthalpy change for the formation of...
The standard heat of formation, ΔH∘f, is defined as the enthalpy change for the formation of one mole of substance from its constituent elements in their standard states. Thus, elements in their standard states have ΔH∘f=0. Heat of formation values can be used to calculate the enthalpy change of any reaction. Consider, for example, the reaction 2NO(g)+O2(g)⇌2NO2(g) with heat of formation values given by the following table: Substance   ΔH∘f (kJ/mol) NO(g)   90.2 O2(g)   0 NO2(g)   33.2 Then the standard heat...
Methanol (CH3OH) has been proposed as an alternative fuel. Calculate the standard enthalpy of combustion per...
Methanol (CH3OH) has been proposed as an alternative fuel. Calculate the standard enthalpy of combustion per gram of liquid methanol. Standard Heats of Formation: CH3OH(l) = –239 kJ/mol O2(g) = 0 kJ/mol CO2(g) = –393.5 kJ/mol H2O(l) = –286 kJ/mol ΔH =_______ kJ/g CH3OH
The standard enthalpy change for the combustion of 1 mole of ethylene is -1303.1 kJ C2H4(g)...
The standard enthalpy change for the combustion of 1 mole of ethylene is -1303.1 kJ C2H4(g) + 3 O2(g) ----> 2 CO2(g) + 2 H2O Calculate the change of Hf for ethylene based on the following standard molar enthalpies of formation. molecules Change in Hf (kJ/mol) CO2 -393.5 H2O -241.8
The enthalpy of combustion (∆Hc) of aluminum borohydride, Al(BH4)3(l), was measured to be -4138.4 kJ/mol [Rulon...
The enthalpy of combustion (∆Hc) of aluminum borohydride, Al(BH4)3(l), was measured to be -4138.4 kJ/mol [Rulon and Mason, J. Am. Chem. Soc.,73, 5491 (1951)]. The combustion reaction for this compound is given by Al(BH4)3(l) + 6 O2(g) → ½ Al2O3(s) + 3/2 B2O3(s) + 6 H2O(l) Given the following additional data, calculate the enthalpy of formation of Al(BH4)3(g). Substance Property Al2O3(s) ∆Hf = -1669.8 kJ/mol B2O3(s) ∆Hf = -1267.8 kJ/mol H2O(l) ∆Hf = -285.84 kJ/mol Al(BH4)3(l) ∆Hvap = 30.125 kJ/mol...
ADVERTISEMENT
Need Online Homework Help?

Get Answers For Free
Most questions answered within 1 hours.

Ask a Question
ADVERTISEMENT