For which of the following equations the change in enthalpy at 1 atm of pressure
ID: 1046843 • Letter: F
Question
For which of the following equations the change in enthalpy at 1 atm of pressure is equal to the standard enthalpy of formation of liquid formic acid HCOOH?a) CO2(g) H2(g) -> HCOOH (I) b) CO(g) H20 -> HCOOH (I) c) C(s) 2H(g) 20 -> (g) HCOOH (I) d) C(g) 2H(g) 20 -> (g) HCOOH (I) e) C(s) H2(g) O2(g) -> HcooH (I) For which of the following equations the change in enthalpy at 1 atm of pressure is equal to the standard enthalpy of formation of liquid formic acid HCOOH?
a) CO2(g) H2(g) -> HCOOH (I) b) CO(g) H20 -> HCOOH (I) c) C(s) 2H(g) 20 -> (g) HCOOH (I) d) C(g) 2H(g) 20 -> (g) HCOOH (I) e) C(s) H2(g) O2(g) -> HcooH (I)
Explanation / Answer
The reaction will be called the standard enthalpy of formation if all the reactants are present in their naturally occuring state
Carbon exists as C(s)
Hydrogen exists as gas H2(g)
Oxygen exists as O2(g)
Hence the reaction must be
C(s) + H2(g) + O2(g) --------- HCOOH(l)
Therefore correct answer must be Option E