CHEMISTRY COMMUNITY

Aarti K Jain 1L

If E is negative, deltaG will be positive and the reaction is unfavorable. If E is positive, delta G will be negative and the reaction is favorable.

Aarti K Jain 1L

If you want to find the new K value when the temperature changes, using the Van't Hoff equation will allow you to find the second K value given you have the original K value.

Aarti K Jain 1L

A unimolecular reaction isn't about collision, but more about a rearrangement of the molecule. For example, decomposition or radioactive decay can occur of a single molecule without any collisions occurring simply because the molecule is breaking apart/rearranging itself into multiple molecules.

Aarti K Jain 1L

Yes, because the rate determining step is the slowest step in the reaction. That rate determining step determines what the rate law is for the entire reaction.

Aarti K Jain 1L

The Van't Hoff equation would be used in order to determine the equilibrium constant as the temperature changes. Therefore, when you have two temperatures and two K values, one can use the Van't Hoff equation.

Aarti K Jain 1L

The set up is:

d[N2O]/dt = k[N2O]
(0.75 - 0.33 M)/dt = (6.8x10^-3/s)(0.33 M)

Solve for dt.

*I am unsure about which concentration is plugged into [N2O], but I assume it is the final concentration.

Hope this helps.

Aarti K Jain 1L

In kinetics, k is the rate constant, whereas K is the equilibrium constant. Also, K = k/k', which means the the equilibrium constant is equal to the ratio of rate constants of the forward (k) and the reverse (k') elementary reactions.

Aarti K Jain 1L

Only add water in a cell diagram if it is being either oxidized or reduced. If not, there is no point in writing it as it only acts as a solvent and writing aqueous implies that water is present.

Aarti K Jain 1L

Well, one way of finding k' would be to set the reverse rate to the forward rate equal at equilibrium. For example, for the reaction A + B --> C + D, the reaction rates at equilibrium are: k[A][B] = k'[C][D]. You would need to know the concentrations of the products and reactants at equilibrium as w...

Aarti K Jain 1L

As was said previously, in a spontaneous reaction, delta G is negative as free energy is released in the reaction. Also, DeltaG = -nFE, which means that for delta G to be negative, E must be positive. The standard potential is relative to electron-pulling power of the cathode, which means that if th...

Aarti K Jain 1L

It seems as though the reaction that is shown is a dissolution, which means that AgBr is dissolving into its respective ions, which are Ag+ and Br-. It's similar to the reaction: NaCl (aq) --> Na+ (aq) + Cl- (aq), where the Na is being oxidized and the chlorine is being reduced. Hope this helps!

Aarti K Jain 1L

A comma is used when both the oxidized species and the reduced species are in the same phase (usually, both are aqueous) for the same half-reaction. A straight line indicates a phase change between the oxidized species and the reduced species in the same half-reaction.

Aarti K Jain 1L

The more negative the standard potential, the more strongly the reducing agent/element.

Aarti K Jain 1L

A thermodynamically stable compound will have a negative standard Gibbs free energy of formation, meaning that it is spontaneous.

A thermodynamically unstable compound will have a positive standard Gibbs free energy of formation, meaning that it is non-spontaneous.

Aarti K Jain 1L

In order to find the oxidation number of Mn in MnO4-, first assume, as was said earlier, that the oxidation number of the oxygen is -2. Since there are four oxygens in the molecule, the total charge from the oxygen is -8. However, the charge of the whole molecule is -1. Therefore, the total charge o...

Aarti K Jain 1L

From the second law of thermodynamics, we know that the natural progression of a system is to an increase in entropy. Therefore, a reaction in which the total entropy naturally increases is spontaneous. In the equation for Gibbs, deltaG = -T[deltaS(tot)] at constant temperature and pressure. As a re...

Aarti K Jain 1L

The more negative the standard potential, the more strongly reducing the element. Those elements are found on the left of the periodic table. The more positive the standard potential, the more strongly oxidizing the element. Those elements are found toward the upper right. Looking at the list of sta...

Aarti K Jain 1L

There is more complexity in the SO2F2, whereas FClO3 doesn't have the same complexity. For the FClO3, the position of the Cl changes, so there are four possible places for the Cl to be. For the SO2F2, the oxygens and fluorines can change positions, so there are more orientations/microstates because ...

Aarti K Jain 1L

In the example of irreversibility (isothermal expansion), the gas isn't doing work on its surroundings as the external pressure is zero. Therefore, P(ΔV) = 0. However, in the reversible example, the gas is doing work on its surroundings. Therefore, the reversible system is always doing more work tha...

Aarti K Jain 1L

Basically, you get to decide what the system is and what the surroundings are depending on what you are doing and what experiment you are running.

Aarti K Jain 1L

Also, I assume that his focus on gases means that we won't need to focus on how the expression applies to liquids and solids for tests and such.

Aarti K Jain 1L

There are different formulas for work depending on the type of work done. In this section, I think that we will be working with the equation:
work = -(Pressure)(Change in Volume)

Aarti K Jain 1L

Heat is the energy that causes changes in a system. Enthalpy is the total state of the system - the heat consumed or released by the system.

Aarti K Jain 1L

For bond enthalpy, you first have to recognize which bonds are broken and which are formed. Then you add the bond enthalpies for the bonds that are broken and do the same for the bonds that are formed. From there, subtract the bond enthalpy of the formed bonds from the bond enthalpy of the broken bo...

Aarti K Jain 1L

In general, when creating ICE tables, you are only looking at the molecules that affect pH. Therefore, if a cation/anion does not appear in the acid/base reaction, then one does not have to take the cation/anion into account.

Aarti K Jain 1L

With regards to Kb, one is looking at the pOH scale instead of the pH scale because OH- ions are produced, not H3O+ during the dissociation/reaction of a base. Therefore, on the pOH scale, having a greater value means that the base is weak.

Aarti K Jain 1L

Each question should give you the temperature at which the equilibrium value (K) occurs. If no temperature occurs, assume 25 degrees Celsius.

Aarti K Jain 1L

Once a reaction has reached equilibrium, it will stay at equilibrium as long as the reaction itself is not affected. Adding a liquid will not change the equilibrium concentrations/pressures of K value so long as the liquid does not react with the gases that have already reacted and reached equilibri...

Aarti K Jain 1L

There really is no significance for using bar for units as opposed to pascals or atm. The textbook writers probably just want to make sure that the reader can use all the different kinds of units and is consistent when using each one. For this particular problem, I would suggest finding K(p) using t...

Aarti K Jain 1L

Also, an applied stress can be caused by changes to the environment, such as compression or temperature. As a result, the reaction will favor the side (either reactants or products) that will reduce the stress caused by that change. For example, if a container is compressed, the reaction occurring w...

CHEMISTRY COMMUNITY

Search found 30 matches

Re: negatives in the equation

Re: Overview

Re: Molecularity

Re: Rate Determining Step

Re: Van't Hoff use

Re: Problem

Re: k & K

Re: Water in a cell diagram

Re: k' Value

Re: Signs of delta G and E

Re: Adding in extra ions

Re: Using commas in cell diagram

Re: Question 14.25 (Sixth Edition)

Re: Spontaneous and unstable

Re: Balancing Charges

Re: Negative Delta G

Re: trends in standard potential

Re: Degeneracy

Re: Work

Re: Surroundings

Re: PΔV for solids and liquids

Re: State Properties

Re: Heat vs Enthalpy

Re: The 3 methods

Re: Weak acid and its salt

Re: pKa and pKb

Re: Temperature for Equilibrium

Re: Adding a liquid

Re: Homework 11.79 6th edition

Re: what is lechatliers principle [ENDORSED]