Enthalpy of combustion of $C H_{4}, C_{2} H_{6}$ and $C_{3} H_{8}$ are -210.8, -368.4 and -526.2 k cal $m o l^{- 1}$ respectively. Enthalpy of combustion of hexane can be predicted as ?

-840 k cal $m o l^{- 1}$

No worries! We‘ve got your back. Try BYJU‘S free classes today!

-684 k cal $m o l^{- 1}$

No worries! We‘ve got your back. Try BYJU‘S free classes today!

-1000 k cal $m o l^{- 1}$

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

None of these

No worries! We‘ve got your back. Try BYJU‘S free classes today!

Open in App

Solution

The correct option is C
-1000 k cal $m o l^{- 1}$

$Δ H_{C} (C_{2} H_{6}) - Δ H_{C} (C H_{4}) = - 368.2 - (- 210.8) = - 157.4 Δ H_{C} (C_{3} H_{8}) - Δ H_{C} (C_{2} H_{6}) = - 526.2 - (- 368.4) = - 157.8 T h u s, a v e r a g e Δ H_{C} (- C H_{2}) = \frac{157.4 + 157.8}{2} = - 157.6 k c a l m o l^{- 1} T h e n, Δ H_{C} (C_{6} H_{14}) = Δ H_{C} (C_{3} H_{8}) + 3 Δ H_{C} (- C H_{2}) = - 526 + 3 (- 157.6) = - 999 k c a l$

Suggest Corrections

Similar questions

Q. Heat of combustion of

C H_{4}

C_{2} H_{6}

and

C_{3} H_{8}

are respectively - 210, - 368.4 and - 526.8 Kcal

m o l_{1}

Hence, heat of combustion of

C_{8} H_{16}

is approximately:

Enthalpy of combustion of carbon, hydrogen and $C_{3} H_{8}$ are $x_{1}, x_{2}$ and $x_{3} m o l^{- 1}$ respectively. Estimate the enthalpy of formation of $C_{3} H_{8}$

Q. The enthalpy change for the reaction

C_{3} H_{8} (g) + H_{2} (g) \to C_{2} H_{6} (g) + C H_{4} (g)

25^{o}

is -55.7 kJ / mol . Calculate the enthalpy of combustion of

C_{2} H_{6} (g)

. The enthalpy of combustion of propane is

- 2220 k J m o l^{- 1}

and enthalpy of

H_{2}

and

C H_{4}

are -285.8 KJ/mol and -890 KJ/mol respectively.

The enthalpy of atomisation of $C H_{4}$ and $C_{2} H_{6}$ are 360 and 620 k cal $m o l^{- 1}$ respectively. The C - C bond energy is expected to be ?

Q. Enthalpy of

C H_{4} + \frac{1}{2} O_{2} \to C H_{3} O H

is negative. If enthalpy of combustion of

C H_{4}

and

C H_{3} O H

are x and y respectively then which relation is correct ?

Join BYJU'S Learning Program

Enthalpy of combustion of CH4,C2H6 and C3H8 are -210.8, -368.4 and -526.2 k cal mol−1 respectively. Enthalpy of combustion of hexane can be predicted as ?

The correct option is C -1000 k cal mol−1 ΔHC(C2H6)−ΔHC(CH4)=−368.2−(−210.8)=−157.4ΔHC(C3H8)−ΔHC(C2H6)=−526.2−(−368.4)=−157.8Thus,average ΔHC(−CH2)=157.4+157.82=−157.6 k cal mol−1Then,ΔHC(C6H14)=ΔHC(C3H8)+3ΔHC(−CH2)=−526+3(−157.6)=−999 k cal

Enthalpy of combustion of $C H_{4}, C_{2} H_{6}$ and $C_{3} H_{8}$ are -210.8, -368.4 and -526.2 k cal $m o l^{- 1}$ respectively. Enthalpy of combustion of hexane can be predicted as ?