During a spontaneous chemical reaction, it is found that äSsys < 0. This means __________
a. äSsurr < 0 and its magnitude is < äSsys.
b. äSsurr < 0 and its magnitude is > äSsys.
c. äSsurr > 0 and its magnitude is < äSsys.
d. äSsurr > 0 and its magnitude is > äSsys.
e. an error has been made, as Ssys > 0 by necessity for a spontaneous process.
Heat
For a system to be spontaneous you want
dStotal = dSsurr + dSsys = >0
Look to see if d doesn't satisfy that.
To understand the answer to this question, we need to consider the concept of entropy (S) in thermodynamics. Entropy is a measure of the randomness or disorder of a system.
In this case, "äSsys" refers to the change in entropy of the system during the spontaneous chemical reaction. When it is stated that "äSsys < 0", it means that the entropy of the system decreases during the reaction.
Now, the second part of the question mentions "äSsurr", which refers to the change in entropy of the surroundings (or environment) during the reaction.
Based on the second law of thermodynamics, for a spontaneous process, the total entropy change of the universe (which includes both the system and the surroundings) must be greater than or equal to zero. In other words, "äStotal = äSsys + äSsurr ≥ 0".
Since "äSsys < 0", if the system's entropy decreases during the reaction, the surroundings must experience an increase in entropy to compensate and satisfy the condition that "äStotal ≥ 0".
Therefore, the correct answer is:
c. äSsurr > 0 and its magnitude is < äSsys.
This means that the entropy of the surroundings increases (äSsurr > 0), but the magnitude of this increase is less than the magnitude of the decrease in entropy of the system (äSsurr < äSsys).