Which of the following statement is incorrect for the reaction? H 2(g)+ Br 2(l) longrightarrow 2 HBr (g); Δr H°=-178.3 kJ mol -1

Question

Which of the following statement is incorrect for the reaction? H 2(g)+ Br 2(l) longrightarrow 2 HBr (g); Δr H°=-178.3 kJ mol -1 (A) The enthalpy change given is equal to Δf H° HBr. (B) Δr H°=2 Δf H° HBr (C) Δf H° of an element in refrence state is taken as zero (D) None of the above

Tardigrade Admin · Accepted Answer

Statement (a) is incorrect.
It's correct form is as follows :
The enthalpy change given, i.e.

Δ_{r} H^{\circ} = - 178.3 k J / m o l

is not equal to

Δ_{f} H^{\circ} H B r

as here two moles, instead of one mole of the product is formed.
Rest other statements are correct.

Q. Which of the following statement is incorrect for the reaction?
$H_{2} (g) + B r_{2} (l) ⟶ 2 H B r (g); Δ_{r} H^{\circ} = - 178.3 k J m o l^{- 1}$

The enthalpy change given is equal to $Δ_{f} H^{\circ} H B r$ .

$Δ_{r} H^{\circ} = 2 Δ_{f} H^{\circ} H B r$

$Δ_{f} H^{\circ}$ of an element in refrence state is taken as zero

None of the above

Statement (a) is incorrect.
It's correct form is as follows :
The enthalpy change given, i.e. $Δ_{r} H^{\circ} = - 178.3 k J / m o l$ is not equal to $Δ_{f} H^{\circ} H B r$ as here two moles, instead of one mole of the product is formed.
Rest other statements are correct.

Q. Which of the following statement is incorrect for the reaction? H2​(g)+Br2​(l)⟶2HBr(g);Δr​H∘=−178.3kJmol−1

The enthalpy change given is equal to Δf​H∘HBr.

Δr​H∘=2Δf​H∘HBr

Δf​H∘ of an element in refrence state is taken as zero