Home
Class 11
CHEMISTRY
The standard enthalpy of formation of oc...

The standard enthalpy of formation of octane `(C_(8)H_(18))` is `-250kJ //mol`. Calculate the enthalpy of combustion of `C_(8)H_(18)`. The enthalpy of formation of `CO_(2)(g)` and `H_(2)O(l)` are `-394 kJ//mol` and `-286kJ//mol` respectively.

A

`- 5200` kJ/mol

B

`- 5726` kJ/mol

C

`- 5476` kJ/mol

D

`- 5310` kJ/mol

Text Solution

Verified by Experts

The correct Answer is:
C

`C_(8)H_(18)(g)+(25)/(2)O_(2)(g)rarr8CO_(2)(g)+9H_(2)O(l)`
`Delta_(r )H^(@)=8xx(-394)+9xx(-286)-(-250)`
`=-5476 " kJ"//"mol"`
Promotional Banner

Topper's Solved these Questions

  • THERMODYNAMICS

    NARENDRA AWASTHI|Exercise Level 1 (Q.1 To Q.30)|6 Videos
  • THERMODYNAMICS

    NARENDRA AWASTHI|Exercise Level 1 (Q.31 To Q.60)|2 Videos
  • STOICHIOMETRY

    NARENDRA AWASTHI|Exercise Level 3 - Subjective Problems|20 Videos

Similar Questions

Explore conceptually related problems

The combustion of one mole of benzene takes place at 298 and 1 atm. After combustion, CO_(2)(g) and H_(2)O(l) are produced and 3267.0 kJ of heat is liberated. Calculate the standard enthalpy of formation. triangle_f H^@ benzene. Standard enthalpies of formation of CO_2(g) and H_20(l) are -393,5 kJ mol ""^(-1) and "-285.83 kJ mol"^(-1) respectively.

The standard enthalpy of formation of hypothetical MgCl is -125kJ mol^(-1) and for MgCl_(2) is -642 kJ mol^(-1) . What is the enthalpy of the disproportionation of MgCl ?

alpha -maltose can be hydrolysed to glucose according to the following reaction. Given Standard enthalpies of formation of C_(12) H_(22)O_(11) (aq) = -2238 kJ/mol Standard enthalpies of formation of H_(2)O (l) = -285kJ//mol Standard enthalpies of formation of C_(6)H_(12)O_(6) (aq) = -1263kJ//mol {:("Time (min)",0,1.0,100),("Conc. Of -maltose(M)",4.0,1.0,0.25):} Which of the following statements(s) is/are true?

Enthalpy of combustion of carbon to CO_(2) is -393.5 kJ mol^(-1). Calculate the heat released upon formation of 35.2 g of CO_(2) from carbon and dioxygen gas.

The standard enthalpies of formation of CO_(2) gas and HCOOH_((l)) are -393.7 kJ mol^(-1) and -409.2 kJ mol^(-1) respectively. Which of the following are correct?

The enthalpy of formation of ammonia is -46.0 KJ mol^(-1) . The enthalpy change for the reaction 2NH_3 rarr N_2 + 3H_2 is

If enthalpy of combustion of carbon to CO_(2) (g) is -394.0kJ mol^(-1) , the enthalpy change for the formation of 17.6 g of CO_(2) from carbon and dioxygen at the same temperature in kJ is

The heats of combustion of carbon,hydrogen and acetylene are -394kJ, -286kJ and -130kJ respectively. Calculate heat of formation of C_(2)H_(2)

The standard enthalpy of formation (Delta H^(0)) at 298K for methane, CH_(4(g)) is 74.8 kJ mol^(1) . The additional information required to determine the average energy for C-H bond formation would be