You visited us 1 times! Enjoying our articles? Unlock Full Access!

Heat of Formation

Calculate the...

Question

Calculate the heat of the formation of anhydrous $A l_{2} C l_{6}$ from the following data:
a. $2 A l (s) + 6 H C l (a q) ⟶ A l_{2} C l_{6} (a q) + 3 H_{2} + 1004.2 k J$
b. $H_{2} (g) + C l_{2} (g) ⟶ 2 H C l (g) + 184.1 k J$
c. $H C l (g) + a q ⟶ H C l (a q) + 73.2 k J$
d. $A l_{2} C l_{6} (s) + a q ⟶ A l_{2} C l_{6} (a q) + 643.1 k J$

Δ_{f} H = - 1352.6 k J m o l^{- 1}

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

Δ_{f} H = + 1352.6 k J m o l^{- 1}

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

Δ_{f} H = - 2638.67 k J m o l^{- 1}

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

None of these

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

Open in App

Solution

The correct option is A $Δ_{f} H = - 1352.6 k J m o l^{- 1}$
As given,
a. $2 A l (s) + 6 H C l (a q) ⟶ A l_{2} C l_{6} (a q) + 3 H_{2} + 1004.2 k J$
b. $H_{2} (g) + C l_{2} (g) ⟶ 2 H C l (g) + 184.1 k J$
c. $H C l (g) + a q ⟶ H C l (a q) + 73.2 k J$
d. $A l_{2} C l_{6} (s) + a q ⟶ A l_{2} C l_{6} (a q) + 643.1 k J$
So for
$2 A l (s) + 3 C l_{2} (g) \to A l_{2} C l_{6}; Δ H_{f} = ?$
From given data
$Δ H_{f} = - (1004.2 - 643.1 + 6 * 73.2 + 3 * 184.1) = - 1352.6 k J / m o l$

Suggest Corrections

Similar questions

A l_{2} C l_{2}

2 A l (s) + 6 H C l (a q) \to A l_{2} C l_{6} (a q) + 3 H_{2} (g), △ H = - 239.76 k c a l

H_{2} (g) + C l_{2} (g) \to 2 H C l (g), △ H = - 44.0 k c a l

H C l (g) + A q \to H C l (a q), △ H = - 17.32 k c a l

A l_{2} C l_{6} (s) + A q \to A l_{2} C l_{6} (a q), △ H = - 153.69 k c a l

{A l}_{2} {C l}_{6}

2 A l (s) + 6 H C l (a q) ⟶ {A l}_{2} {C l}_{6} (a q) + 3 H_{2} (g), Δ H = - 239.76 k c a l

H_{2} (g) + {C l}_{2} (g) ⟶ 2 H C l (g); Δ H = - 44.0 k c a l

H C l (g) + A q ⟶ H C l (a q); Δ H = - 17.32 k c a l

{A l}_{2} {C l}_{6} (s) + A q ⟶ {A l}_{2} {C l}_{6} (a q); Δ H = - 153.69 k c a l

Δ_{f} H^{⊖}

C O

\frac{1}{2} Δ_{f} H^{⊖} (C O_{2})

\frac{1}{2} Δ_{c} H^{⊖} (g r a p h i t e)

Δ_{f} H^{⊖} (C O_{2}) - Δ_{f} H^{⊖} (g r a p h i t e)

Δ_{c} H^{⊖} (g r a p h i t e) - Δ_{c} H^{⊖} (C O) ?

C H_{3} O H (1) + \frac{3}{2} O_{2} (g) \to C O_{2} (g) + 2 H_{2} O (I); Δ, H^{⊖} = - 726 k J m o l^{- 1}

C (g r a p h i t e) + O_{2} (g) \to C O_{2} (g); Δ_{c} H^{⊖} = - 393 k J m o l^{- 1}

H_{2} (g) + \frac{1}{2} O_{2} (g) \to H_{2} O (I); Δ_{f} H^{⊖} = - 286 k J m o l^{- 1}

{C H}_{3} O H (l)

H_{2} (g) + C l_{2} (g) \to 2 H C l (g)

Δ H

- 44

Join BYJU'S Learning Program