For a certain reaction- - H0 and - S0 respectively are 400 kJ and 200 J-Mole-K- The process is non-spontaneous at-

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Standard XII

Chemistry

Spontaneity

For a certain...

Question

For a certain reaction, $Δ H^{0}$ and $Δ S^{0}$ respectively are 400 kJ and 200 J/Mole/K. The process is non-spontaneous at:

2100 K

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2010 K

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1990 K

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2020 K

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Solution

The correct option is B 1990 K
$Δ G^{0} = Δ H^{0} - T Δ S^{0}$
Just non- spontaneous means $Δ G^{0} = 0$
Hence,
$Δ H^{0}$ = $T Δ S^{0}$
$T = \frac{400 \times 10^{3}}{200}$ $= 2000 K$
Hence, for non-spontaneous, correct $T$ among above is $1990 K$ .

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For a certain reaction, ΔH0 and ΔS0 respectively are 400 kJ and 200 J/Mole/K. The process is non-spontaneous at:

The correct option is B 1990 KΔG0=ΔH0−TΔS0Just non- spontaneous means ΔG0=0 Hence, ΔH0 = TΔS0T=400×103200 =2000 KHence, for non-spontaneous, correct T among above is 1990K.

For a certain reaction, $Δ H^{0}$ and $Δ S^{0}$ respectively are 400 kJ and 200 J/Mole/K. The process is non-spontaneous at:

The correct option is B 1990 K
$Δ G^{0} = Δ H^{0} - T Δ S^{0}$
Just non- spontaneous means $Δ G^{0} = 0$
Hence,
$Δ H^{0}$ = $T Δ S^{0}$
$T = \frac{400 \times 10^{3}}{200}$ $= 2000 K$
Hence, for non-spontaneous, correct $T$ among above is $1990 K$ .