Question

If delta H= -70.0 kJ and delta S = -0.400 kJ the reaction is spontaneous below a certain temperature. Calculate the temperature in Kelvins.

Answer 1

\(\Delta G=\Delta H-T\Delta S\)

spontaneity implies that \(\Delta G<0\)

set: \(\Delta G=\Delta H-T\Delta S=0\)

plug your values in and solve for T

Answer 2

So it would be 280 K?

Answer 3

Thats not what i got, double-check your algebra

Answer 4

I got 28?

Answer 5

\(-70.0-(T*-0.4)=0\)

\(-70.0+T*0.4=0\)

\(0.4T=70\)

\(T=\dfrac{70}{0.4}=175~K\)

Answer 6

how did T become positive?

Answer 7

I see!!

Answer 8

The two negative signs cancelled out: -(-0.4)=0.4

Answer 9

Thank you so much!!!

Answer 10

no problem!