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Max Mazo 2C

Why do you use k2/k1?

Max Mazo 2C

Where can I find Lyndon's review test?

Max Mazo 2C

Where can I find this practice final?

Max Mazo 2C

Since the reaction has multiple steps, there will be multiple transition states, which means multiple energy barriers.

Max Mazo 2C

Catalysts provide an alternate pathway for the reactants which requires less energy than without them.

Max Mazo 2C

The transition state is the area between reactants and products where there is an energy barrier(activation energy) the must be met to complete the reaction. It is always the peak of the energy profile because all reactions have an energy barrier.

Max Mazo 2C

It's given in units of M because we're studying the change in concentration, but there are questions using rate equations in the homework that involve mass of a given substance.

Max Mazo 2C

Since Dr. Lavelle covered the derivation in class, you should assume it's fair game for the final just in case. It's on the equation sheet so you should be fine as long as you know what it is.

Max Mazo 2C

Expanding on this, what is a pseudo first order reaction?

Max Mazo 2C

He hasn't asked for derivations on any of our tests so far, but knowing the derivation may help with applying the equation or answering conceptual questions.

Max Mazo 2C

The instantaneous rate is the rate at one point one the reaction. More specifically, we use the instantaneous rate at time=0 so that no products have been formed and we can define the rate only with the concentration of the reactants.

Max Mazo 2C

Are you talking about a as in - $\frac{1}{a}\frac{d[A]}{dt}$ ? That a would be the molar coefficient of reactant A.

Max Mazo 2C

If you remember from 14A as long as we are studying something in a gaseous state we can use partial pressure or concentration to calculate Q since the pressure of gas will also affect the reaction direction.

Max Mazo 2C

Using the Nernst equation you can find the concentration of H+ ions which you can use to find pH. There was a homework problem that gave you pH and asked to find E, try looking at the solution for that if you're still confused.

Max Mazo 2C

The anode is usually on the left but if you're not sure you can just check which has the higher E^o value

Max Mazo 2C

It's unlikely the derivations will appear on a test since we're given the equations, but as the above users have said it would be helpful to know them since understanding them would help you know how to apply them.

Max Mazo 2C

Dr. Lavelle has mentioned in lecture that we won't need to to ICE tables

Max Mazo 2C

The lowercase letters a, b, c, and d all refer to the molar coefficients of each part of the reaction, and the upper case letters A, B, C, and D refer to the components of the reaction, with C and D as products and A and B as reactants.

Max Mazo 2C

Is residual entropy related to how there is a standard entropy of formation for gas molecules like O₂ that are already in their standard state?

Max Mazo 2C

Can someone explain why entropy of a "perfect crystal" is 0 (S=0)? At 0K there is no movement of atoms so there is only one possible state for each molecule in a crystal, so it is perfectly ordered and we can know the exact position of everything. Since there is only one possible state, d...

Max Mazo 2C

Because there is no movement at 0K, there is only one possible state (so w=1), which makes entropy equal to 0.

Max Mazo 2C

To piggyback on the post above, the total ∆G of the two reactions combined must still be negative, so the spontaneous reaction must release more free energy than the non-spontaneous reaction uses.

Max Mazo 2C

Can someone explain how it depends on temperature? Since T isn't part of the equation, are there different values of K_b depending on the temperature?

Max Mazo 2C

Potential disorder is another way of saying the amount of potential different states of a system, so it is the same as degeneracy. This shouldn't be important though since Dr. Lavelle wants to avoid using the term disorder altogether.

Max Mazo 2C

I think Dr. Lavelle said in lecture on Wednesday that the solution is so dilute that that salt(in the case of acid-base reactions) has very little impact on the specific heat capacity and you can just use the capacity of the solvent.

Max Mazo 2C

Using the ideal gas equation, $n=\frac{PV}{RT}$ , so the number of moles of a certain gas can change as pressure or volume change.

Max Mazo 2C

Adding to the other posts, when we calculate the change in internal energy of a system, ∆U = Q + W, Q represents the energy that the system either loses or gains as heat, not the heat the system possesses.

Max Mazo 2C

Another way to think about this is to remember that enthalpy is a state function, so the path taken doesn't matter. Since sublimation is changing directly from a solid to a vapor, the beginning and end points are the same as a a substance that goes through fusion and then vaporization, so the ∆H of ...

Max Mazo 2C

If something behaves like an ideal gas, it means it follows the ideal gas law PV=nRT.

Max Mazo 2C

Do we need to bring a physical copy of the textbook to discussion sections, or can we use a pdf on our laptops?

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Re: Arrhenius Equation

Re: Lyndon Review Test, Question 7a [ENDORSED]

Re: Negative activation energy?

Re: Activation Energy

Re: catalyst

Re: Transition State

Re: Definition of Reaction Rate

Re: Half-Life of Zero Order

Re: Pseudo First Order Reaction

Re: Rate equations

Re: Instantaneous Rate

Re: a value

Re: Pressure in calculating Q

Re: Nernst Equation to find pH

Re: anode vs cathode in non standard cell diagram

Re: Derivation

Re: Finding K

Re: Reaction Coefficient, Q

Re: Residual Entropy

Re: Perfect Crystal

Re: Third Law

Re: About entropy and gibbs free energy

Re: Boltzmann Equation Clarification

Re: Positional disorder?

Re: Specific Heat Capacity

Re: Molar heat capacity

Re: State function in relation to heat

Re: Enthalpy of sublimation

Re: Ideal Gas

Having the textbook in discussion