`C_(4)H_(10)+(13)/(2)O_(2)(g)rarr4CO_(2)(g)+5H_(2)O(l), DeltaH =- 2878 kJ`
`DeltaH` is the heat of……….of butane gas.

H_(2)O(g) rarr H_(2)O(l), DeltaH =- 40.7 kJ DeltaH is the heat of……………….of water.

H_(2)O(l) rarr H_(2)O(g), DeltaH = +40.7 kJ DeltaH is the heat of ……………..of water.

H_(2)O(l) rarr H_(2)O(s), DeltaH =- 6.01 kJ DeltaH is the heat of ……………….of water.

H_(2)O(s) rarr H_(2)O(l), DeltaH = 6.01 kJ DeltaH is the heat of …………………of ice.

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

CH_(4)(g) +2O_(2)(g) rarr CO_(2)(g) +2H_(2)O(l), DeltaH =- 890 kJ what is the calorific or fuel value of 1kg of CH_(4) ?

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: