November 30, 2022, 04:34:24 AM
Forum Rules: Read This Before Posting

### Topic: Entropy  (Read 722 times)

0 Members and 1 Guest are viewing this topic.

#### Judy

• Regular Member
• Posts: 38
• Mole Snacks: +0/-0
##### Entropy
« on: January 17, 2022, 11:37:09 AM »
Which response includes all of the following processes that are accompanied by an increase of entropy?

I) NaCl(s) ----H20---> Na+(aq) + Cl-(aq)

II) CaSO4(s) ---H20---> Ca +2(aq) + SO4 -2(aq)

III) KNO3 (s) ---H20---> K +1(aq) + NO3 -1(aq)

the answer is I and III.

Why does II decrease, just like I and III, they turn from 1 to 2 molecules?

#### Babcock_Hall

• Chemist
• Sr. Member
• Posts: 5335
• Mole Snacks: +304/-22
##### Re: Entropy
« Reply #1 on: January 17, 2022, 11:39:37 AM »
What is different about the ions in II vs. I and III?  Once you identify this difference, think about what the difference affects.

#### Judy

• Regular Member
• Posts: 38
• Mole Snacks: +0/-0
##### Re: Entropy
« Reply #2 on: January 17, 2022, 10:33:49 PM »
Is it because I and III are belong to IA group while II belong to IIA group? If so, why IIA group tend to decrease in entropy when dissolved in water? Thanks.

#### Babcock_Hall

• Chemist
• Sr. Member
• Posts: 5335
• Mole Snacks: +304/-22
##### Re: Entropy
« Reply #3 on: January 18, 2022, 09:34:44 AM »
How many charges does the calcium ion have?  How many charges does the sodium ion have?  Same questions for sulfate vs. chloride.  Besides the ions, what else is present in a solution?  How might this something else behave in response to the presence of the ions?