New User Special Price Expires in

Let's log you in.

Sign in with Facebook


Don't have a StudySoup account? Create one here!


Create a StudySoup account

Be part of our community, it's free to join!

Sign up with Facebook


Create your account
By creating an account you agree to StudySoup's terms and conditions and privacy policy

Already have a StudySoup account? Login here

Chem 113, week 2

by: Alexis Darling

Chem 113, week 2 CHEM 113

Alexis Darling
GPA 4.0

Preview These Notes for FREE

Get a free preview of these Notes, just enter your email below.

Unlock Preview
Unlock Preview

Preview these materials now for free

Why put in your email? Get access to more of this material and other relevant free materials for your school

View Preview

About this Document

Week 2 notes, organized by textbook chapter
General Chemistry II
Ingrid Marie Laughman
Class Notes
25 ?




Popular in General Chemistry II

Popular in Department

This 2 page Class Notes was uploaded by Alexis Darling on Thursday January 28, 2016. The Class Notes belongs to CHEM 113 at Colorado State University taught by Ingrid Marie Laughman in Fall 2015. Since its upload, it has received 16 views.


Reviews for Chem 113, week 2


Report this Material


What is Karma?


Karma is the currency of StudySoup.

You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!

Date Created: 01/28/16
12.3 Each substance has a standard molar entropy which tells how dispersed the energy is in  one mole of the substance at 1 bar of pressure and 25ºC­­conditions at which it remains in its  standard state. This is influenced by the molecules’ molar masses (the greater mass, the more  entropy), the amount of organization of the structure if a solid (which impacts how rigid the  substance is; think about a bunch of things held together tightly, they cannot move as much as if  they were loosely connected, therefore the more rigid the less microstates, less entropy), and the  ways all the molecules interact with each other within the substance. These interactions depend  on rotational motion, or how they bump into each other, which changes with the ways that their  mass is distributed through the molecule. Longer molecules have more ways that they can rotate  and tumble than molecules with more centralized mass (think of a tumbling pen vs a rolling  sphere (a sphere really only has a couple ways to move)) The biggest factor into standard  entropies is whether the substance in its standard state is a solid (low entropy), liquid (more  entropy), or gas (very high entropy).  Considering entropy change, entropy increases directly with temperature, volume, and  the number of particles. In general, the more microstates it has as possibilities, the higher the  entropy. 12.4 A spontaneous reaction will always result in greater distribution of energy in the universe (increase in entropy). Therefore ΔS univis always positive after a spontaneous process, and  considering the reverse, is always negative after a nonspontaneous process; the second law of  thermodynamics.  Looking at a reaction of 3 moles of gaseous reactants to 1 mole of gaseous and 2 moles of liquid products, we know that some gaseous molecules turned into liquid molecules, a phase  change which means less entropy (molecules cannot move as freely in a liquid compared to in a  gas). This negative entropy is of the system, but the entropy of the universe must be positive  because it is a spontaneous reaction (second law). To get ΔS univΔS +sys, thsurrange in  entropy of the surroundings must be a bigger positive than the negative change of the system to  equal a positive change in the universe. (pos# = neg# + big pos#) The increase in entropy of the  surroundings is seen through the heat released (ΔH) –and remember that a negative ΔH (products minus reactants) means reactants had more energy than products so heat was released and  therefore energy is gained into the surroundings; positive entropy for surroundings. This  reasoning applies to all variations of positive/negative changes in entropy of system and universe and surroundings. q  for a reversible process is the number of moles of reactant multiplied by how much  rev energy that substance requires to complete the change which increases entropy, but the change  which it undergoes can be reversed so that the substance fully returns back to its initial state.  Putting q into equations for ΔS  asysΔS , q csurre made to describe system or surroundings  based on whether it is made positive or negative. If the system loses heat then q is negative ansys  q surr  positive, because the energy moved into the surroundings and was gained positively by the surroundings. The opposite for if the system gains heat. 12.5 The change in entropy is solely dependent on its initial and final states, no matter how it  arrived at these states. Under standard conditions, the number of moles of reactant/product can  be multiplied by its standard molar entropy to achieve the total value for entropy of the  reactant/product to be entered into the equation ΔS =S rxn final initial 12.6 The entropy change of the surroundings depends solely on whether the reaction is  exothermic or endothermic, causing a positive and negative entropy change for the surroundings, respectively. Because the energy gained by the surroundings in an exothermic reaction must be  lost by the system ­and the opposite for endothermic­, the heat of the surroundings can be related as exactly the negative of the enthalpy change of the system. Assuming the process is reversible,  we can plug (­ΔH )intsys   equation for the change in entropy of surroundings in place of the  q surrthat we get ΔS = ­ΔHsurr Then syscing this little equation in for ΔS surr  the overall  equation ΔS univΔS +sys, wesurr achieve an equation which uses values from just the system  to relate to the universe (ΔS univΔS ­sys /T).sys Gibb’s free energy is the value that describes the amount of energy with the ability to do  work from processes that occur at a held temperature and pressure. This ΔG is directly  sys  proportional to the ΔS univ using –T as a multiplier. Because the multiplier is negative, they relate  as opposites (when G is positive, S is negative, when G is negative, S is positive). Taking the last equation from the above paragraph and multiplying it by T yields an equation with ΔS univ –T)  which we just found is what equals ΔG . Plugging G in results in the simplified equation of  sys ΔG=ΔH­TΔS which can be modified to calculate standard values of a reaction in addition to  values for the system. Standard free energy of formation (ΔGº) is basedfon the energy change when one mole  of a substance forms from the elements that make it up, all from their standard states.  Overall, an increase in enthalpy (H: energy inside a system) leads to some energy  available for use as work (G) and some that simply goes off as heat (T) and into entropy (S:  accessing more microstates). This is seen through the equation that was reached in the paragraph  of Gibb’s free energy which, when you move the –TΔS to the other side, becomes ΔH=ΔG+TΔS.


Buy Material

Are you sure you want to buy this material for

25 Karma

Buy Material

BOOM! Enjoy Your Free Notes!

We've added these Notes to your profile, click here to view them now.


You're already Subscribed!

Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'

Why people love StudySoup

Bentley McCaw University of Florida

"I was shooting for a perfect 4.0 GPA this semester. Having StudySoup as a study aid was critical to helping me achieve my goal...and I nailed it!"

Jennifer McGill UCSF Med School

"Selling my MCAT study guides and notes has been a great source of side revenue while I'm in school. Some months I'm making over $500! Plus, it makes me happy knowing that I'm helping future med students with their MCAT."

Jim McGreen Ohio University

"Knowing I can count on the Elite Notetaker in my class allows me to focus on what the professor is saying instead of just scribbling notes the whole time and falling behind."


"Their 'Elite Notetakers' are making over $1,200/month in sales by creating high quality content that helps their classmates in a time of need."

Become an Elite Notetaker and start selling your notes online!

Refund Policy


All subscriptions to StudySoup are paid in full at the time of subscribing. To change your credit card information or to cancel your subscription, go to "Edit Settings". All credit card information will be available there. If you should decide to cancel your subscription, it will continue to be valid until the next payment period, as all payments for the current period were made in advance. For special circumstances, please email


StudySoup has more than 1 million course-specific study resources to help students study smarter. If you’re having trouble finding what you’re looking for, our customer support team can help you find what you need! Feel free to contact them here:

Recurring Subscriptions: If you have canceled your recurring subscription on the day of renewal and have not downloaded any documents, you may request a refund by submitting an email to

Satisfaction Guarantee: If you’re not satisfied with your subscription, you can contact us for further help. Contact must be made within 3 business days of your subscription purchase and your refund request will be subject for review.

Please Note: Refunds can never be provided more than 30 days after the initial purchase date regardless of your activity on the site.