Home
Class 12
CHEMISTRY
Calculate the heat of formation of metha...

Calculate the heat of formation of methane in `kcalmol^(-1)` using the following thermo chemical reactions
`C(s)+O_(2)toCO_(2)(g) , DeltaH=-94.2 kcal mol^(-1)`
`H_(2)(g)+1/2O_(2)(g)toH_(2)O(l) , DeltaH=-68.3 kcal mol^(-1)`
`CH_(4)(g)+2O_(2)(g)toCO_(2)(g)+2H_(2)O(l) , DeltaH=-210.8 kcal mol^(-1)`

Text Solution

Verified by Experts

The correct Answer is:
`-20`
`C(s) + O_2 (g) to Ca_(2) (g) + 94.2 ` Kcal `" "….(1)`
`H_2 (g) + 1/2 O_2 (g) to H_2 O (l) + 68.3 kcal " "….(2)`
`CH_4 (g) + 2O_2 (g) to CO_2 (g) + 2H_2 (l) + 210.8 kcal " "….(3)`
The required equation is
`C(g) + 2H_2 (g) to CH_4 (g)`
so, `DeltaH_f = Delta H_l + (2xx DeltaH_2) - Delta H_3 =-20 "kcal mol"^(-1)`.
Promotional Banner

Topper's Solved these Questions

  • MOCK TEST 5

    VMC MODULES ENGLISH|Exercise CHEMISTRY (SECTION 2)|5 Videos

  • MOCK TEST 4

    VMC MODULES ENGLISH|Exercise CHEMISTY (SECTION 2)|5 Videos

  • MOCK TEST 6

    VMC MODULES ENGLISH|Exercise CHEMISTRY (SECTION 2)|5 Videos

Similar Questions

Explore conceptually related problems

Calculate enthalpy of formation of methane (CH_4) from the following data : (i) C(s) + O_(2)(g) to CO_(2) (g) , Delta_rH^(@) = -393.5 KJ mol^(-1) (ii) H_2(g) + 1/2 O_(2)(g) to H_(2)O(l) , Deta_r H^(@) = -285.5 kJ mol^(-1) (iii) CH_(4)(g) + 2O_(2)(g) to CO_(2)(g) + 2H_(2)O(l), Delta_(r)H^(@) = -890.3 kJ mol^(-1) .

Using the following thermochemical data. C(S)+O_(2)(g)rarr CO_(2)(g), Delta H=94.0 Kcal H_(2)(g)+1//2O_(2)(g)rarr H_(2)O(l), Delta H=-68.0 Kcal CH_(3)COOH(l)+2O_(2)(g)rarr 2O_(2)(g)rarr 2CO_(2)(g)+2H_(2)O(l), Delta H=-210.0 Kcal The heat of formation of acetic acid is :-

Given that: i. C(s) + O_(2)(g) rarr CO_(2)(g) , DeltaH =- 94.05 kcal ii. H_(2)(g) +(1)/(2) O_(2)(g) rarr H_(2)O(l), DeltaH =- 68.32 kcal iii. C_(2)H_(2)(g) +(5)/(2) O_(2)(g) rarr 2CO_(2)(g) +H_(2)O(l), DeltaH =- 310.62 kcal The heat of formation fo acetylene is

Given that: i. C(s) + O_(2)(g) rarr CO_(2)(g) , DeltaH =- 94.05 kcal ii. H_(2)(g) +(1)/(2) O_(2)(g) rarr H_(2)O(l), DeltaH =- 68.32 kcal iii. C_(2)H_(2)(g) +(5)/(2) O_(2)(g) rarr 2CO_(2)(g) +H_(2)O(l),DeltaH =- 310.62 kcal The heat of formation fo acetylene is

Find the heat of formation of ethyl alcohol for following data C(s) +O_(2)(g) rarr CO_(2)(g) DeltaH =- 94 kcal H_(2)(g) +1//2O_(2)(g) rarr H_(2)O(l), DeltaH =- 68 kcal C_(2)H_(5)OH(l)+3O_(2)(g) rarr 2CO_(2)(g) +3H_(2)O(l) DeltaH =- 327 kcal

C(s)+O_(2)(g)toCO_(2)(g),DeltaH=-94 kcal 2CO(g)+O_(2)to2CO_(2),DeltaH=-135.2 kcal The heat of formation of CO(g) is

Calculate heat of formation of KOH(s) using the following equations K(s) +H_(2)O(l) +aq rarr KOH(aq)+1//2 H_(2)(g),DeltaH =- 48.0 kcal …(i) H_(2)(g) +1//2O_(2)(g) rarr H_(2)O(l),DeltaH =- 68.4 kcal …(ii) KOH(s) +(aq) rarr KOH(aq),DeltaH =- 14.0 kcal ....(iii)

Given that: 2C(s)+O_(2)(g)to2CO_(2)(g)" "(DeltaH=-787kJ) . . . (i) H_(2)(g)+1//2O_(2)(g)toH_(2)O(l)" "(DeltaH=-286kJ) . . . (ii) C_(2)H_(2)+2(1)/(2)O_(2)(g)to2CO_(2)(g)+H_(2)O(l)" "(DeltaH=-1310kJ) . . .(iii) The heat of formation of acetylene is:

Calculate the heat of formation of acetic acid form the following date: a. CH_(3)COOH(l) +2O_(2)(g) rarr 2CO_(2)(g) +2H_(2)O(l)DeltaH^(Theta) =- 200.0kcal b. C(s) +O_(2) (g) rarr CO_(2)(g), DeltaH^(Theta) =- 94.0 kcal c. H_(2)(g) +(1)/(2)O_(2)(g) rarr H_(2)O(l), DeltaH^(Theta) =- 68.0 kcal

Calculate the heat of formation of acetic acid form the following data: a. CH_(3)COOH(l) +2O_(2)(g) rarr 2CO_(2)(g) +2H_(2)O(l)DeltaH^(Theta) =- 200.0kcal b. C(s) +O_(2) (g) rarr CO_(2)(g), DeltaH^(Theta) =- 94.0 kcal c. H_(2)(g) +(1)/(2)O_(2)(g) rarr H_(2)O(l), DeltaH^(Theta) =- 68.0 kcal