Question

You mix hydrogen and chlorine gas in a test tube with a cork in it. Then you shine blue light on it and it detonates and shoots the cork across the room. Consider the hydrogen and the chlorine (and the product) to be the system.

a)Has Work Been Done? If so, on the system or the surrondings?

b) Write the reaction.

c) What is the sign of delta H? How would you know?

d) What is the sign of delta G? How would you know?

e) What is the sign of delta S sys? How would you know?

f) What is the sign of delta Ssurroundings? How would you know?

g)What is the sign of delta Suniverse? How would you know?

Please explain each step, thanks!

Answer 1

a) Work been done on the surroundings   [as volume has increased and cork goes out]

b) H₂ +Cl₂ = 2HCl

c) It is an exothermic reaction, so, sign of delta H is negative.

d) It is an spontaneous reaction so, sign of delta G is negative.

e) delta S_sys = dq/T, It is an exothermic reaction, so, dq = -ve for the system and thus the sign of delta S sys is negative.

f) delta S_surr = dq/T, It is an exothermic reaction, so, dq = +ve for the surroundings and thus the sign of delta S surroundings is positive.

g) It is an spontaneous reaction so, sign of delta Suniverse must be positive.