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

Byju's Answer

Standard XII

Chemistry

Heat Capacity at Constant Pressure

The molar hea...

Question

The molar heat capacities at constant pressure (assume constant with respect to temperature) of $A, B$ and $C$ are in the ration of $1.5 : 3.0 : 2.0$ .
If enthalpy change for the exothermic reaction $A + 2 B \to 3 C$ at $300 K$ is $- 10 k J / m o l$ & $C_{p, m} (B)$ is $300 J / m o l$ then enthalpy change at $310 K$ is:

- 8.5 k J / m o l

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

8.5 k J / m o l

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

- 11.5 k J / m o l

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

none of these

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

Open in App

Solution

The correct option is C $- 11.5 k J / m o l$
$△ H = n C_{p} △ T$ and
$C_{p, m} (B)$ is $300 J / m o l$ so by their ration
$C_{p, m} (C)$ is $200 J / m o l$ and
$C_{p, m} (A)$ is $150 J / m o l$ .
$△ H_{300 K} = - 10 K J$
And $△ H_{310 K} - △ H_{300 K} = (3 * 200 - 2 * 300 - 1 * 150) * △ T = - 1500$
$= - 1.5$ kJ/mole
So for reaction enthapy change at 310K is -
$△ H_{310 K} = - 1.5 - 10 = - 11.5$ KJ/mole.

Suggest Corrections

Similar questions

Q. The molar heat capacities at constant pressure (assume constant with respect to temperature) of A, B and C are in ratio of

1.5 : 3.0 : 2.0

. If enthalpy change for the exothermic reaction

A + 2 B \to 3 C

300 K

- 10 k J / m o l

and

C_{p, m} (B)

300 J / m o l

then enthalpy change at

310 K

is:

Q. The molar heat capacities at constant pressure for

A, B

and

C

are

3, 1.5

and

2

J/K mol. The enthalpy of reaction and entropy of reaction,

A + 2 B \to 3 C

are

20

kJ/mol and

20

J/K mol at

300 K

Calculate

Δ G

(in kJ/mol) for the reaction,

\frac{1}{2} A + B \to \frac{3}{2} C

Q. Calculate the change in entropy when 1 mol of solid iodine at a temperature of 360 K is heated at constant pressure to produce liquid iodine at a temperature of 410 K. The constant pressure molar heat capacity of solid iodine is 54.44 J

K^{- 1}

m o l^{- 1}

and liquid iodine is 80.67 J

K^{- 1}

m o l^{- 1}

.
The melting point of iodine is 387 K and molar enthalpy of fusion of iodine is 7.87 kJ/mol.

If $Δ H_{v a p o r i s a t i o n}$ of substance X(1) (molar mass: 30 g/mol) is 300 J/g at its boiling point 300 K, then molar entropy change for reversible condensation process is

Q. The molar heat capacities of Iodine vapour and solid are

7.8

and

14 c a l / m o l

respective enthalpy of sublimation of iodine is

6096 c a l / m o l

200^{\circ} C

, then what is

Δ H

the value at

250^{\circ} C

in cal/mol.

Join BYJU'S Learning Program

The molar heat capacities at constant pressure (assume constant with respect to temperature) of A,B and C are in the ration of 1.5:3.0:2.0. If enthalpy change for the exothermic reaction A+2B→3C at 300K is −10 kJ/mol & Cp,m(B) is 300J/mol then enthalpy change at 310K is: