CHEMISTRY COMMUNITY

Samira 2B

That would mean that the rate would quadruple or multiply by 6.

If you increase your reactant for a second order, that means that the rate would be increased by the square of however much you increased your reactant.

Samira 2B

Electrostatic Attraction has to do with nucleophilic substitution.

It is when a nucleophile attracts an electrophile to the point where a part of the molecule leaves thus, substituting it.

Samira 2B

If it is 0th order, then it would just be M/s.
For 1st order, it would just be 1/s.
For 2nd order, it would just be M^-1/s.

So, the shortcut is to subtract the exponent of M (1) by the order that the reaction is.

Samira 2B

To use Cp or Cv, you would have to have constant pressure or constant volume, respectively.

Samira 2B

Why do we set the rate law equal to the formation of product in the pre-equilibrium approach?

Samira 2B

In the integration for the 2nd order rxn, where does the negative go?

Samira 2B

I understand the concept of intermediate species. I just do not get how just from the NO2 eqn and the rate eqn, we got that an intermediate species is needed. In the lecture notes, Lavelle states that "NO2 cannot form NO and CO2 so there must be an intermediate species" but in the eqn itse...

Samira 2B

Also, I used a ratio instead of the actual values given and I got the wrong answer? Why is that?

Samira 2B

Why can't we use the same trick that was used in 27 to determine the half-lives for the times that are multiples of 2?

Samira 2B

If you look at page 631 in the chemistry textbook it shows you in the table.

However, the graph itself has an x-axis of time and a y-axis of the concentration of A at time t with a slope that is equal to -k and a y-intercept of the initial concentration of A.

Samira 2B

It is because that accounts for the change in reactants going to products. Since, products is produce that means the reactants must be reduced. So, you would subtract the 0.068 from the initial reactant concentration.

Samira 2B

In the solutions manual, it says that the n=1. However when I separate the rxn into two half-rxn, the n=2?

Samira 2B

Why can you include concentration and partial pressure when calculating the Q of a rxn?

Samira 2B

In the problem I am referring to, there is an equation given where it can go either way. So it is not as easy as looking at which species is oxidized or reduced( or which species is losing or gaining electrons). What I have figured out is that the anode usually has the lower E of cell? Is that a goo...

Samira 2B

How do you tell which equation is the anode and which is the cathode ?

Samira 2B

When do you add Pt(s) to the cell notation? Also, how do you recognize the species that you would put in that place rather than the Pt(s) in the equation?

Samira 2B

What does the book mean when it takes about "pushing and pulling" regarding to the potential difference?

When it states that a rxn with a lot of pushing and pulling power generates high potential difference or a high voltage.

Samira 2B

In a calorimetry problem where ice with a temperature below 0 C is put into water and you are asked to find the final temperature, would you have to have 3 q's for ice: one for the change of heat for ice to 0, the H of fusion and then the change of heat from 0 to the final temperature? or would you ...

Samira 2B

I don't understand how the second and third equations relate to the first one. How does that help us find the answer?

Samira 2B

As Lyndon said in the review, water can evaporate in a room that is room temperature without having to reach boiling point. If you think of the temperature change graphs, a phase change is one where the temperature does not have to change. Thus, the temperature does not have to change for there to b...

Samira 2B

How do we tell if something will become more or less stable as T increases? Don't we not have enough information to tell that?

Samira 2B

Why do we have to account for the entropy of the cooling process when finding the standard entropy of vaporization of water?

Samira 2B

The entropy of a room may decrease with the cooling of the system. However, that does not mean that the whole system would have the entropy decrease. The heat particles just flow to a different object. DeltaS means the change in total entropy as the energy of contents of the two components change so...

Samira 2B

For the midterm, we will not need to know any of the equations (just the connections between the variations), right? Or will not all of them be on the eqn sheet?

Samira 2B

"Energy is free to do all useful work" so the Gmax is just when the work stops being useful with the process.

Samira 2B

If you think about it on the graph that Dr. Lavelle showed us, there is a minimum to the parabolic curve meaning that the free energy of process cannot go below it. The process itself is at equilibrium so, it cannot spontaneously change and if work is put into it it will only be able to go up on the...

Samira 2B

Nevermind I just answered this for myself.

On the graph, a process that leads towards equilibrium is spontaneous while one that leads away equilibrium is non-spontaneous.

Samira 2B

During lecture, there was a graph presented showing spontaneous processes as going down a parabolic curve. Does that non-spontaneous processes happen at equilibrium?

Samira 2B

I was reading the textbook and I am a bit confused on the Clausius Inequality and the logic of getting to it. I understand in what context we would use this equation in but not the concept itself.

Samira 2B

After the introduction of Boltzmann Equation, there were some notes about error in the thermodynamic property and in the statistical. I do not really understand this concept of small and large "error"

Samira 2B

Why is the net production of gas 2/3?

Samira 2B

For a. when calculating bond enthalpies one finds the enthalpy of formation for water in its gas state. However, the equation has water in its liquid state. So, how do we know that water is in its gas state versus knowing it is in its liquid state?

Samira 2B

So, the system being at equilibrium means that it is a reversible process?

Samira 2B

This is from the lecture notes on Friday. Do we only use the work equation when the system is at equilibrium? Because that is when we use the derivative for the small changes in V that leads to the integral of the work eqn.

Samira 2B

For this problem, why is the heat added (947 kJ) negative? I thought when you add heat to a system it is supposed to be positive?

Samira 2B

I read about this in the textbook and I understand that you are supposed to use two different equations for each but what is the difference between these two processes?

Samira 2B

An open system is one that can exchange matter and energy with its surroundings. A closed system is one that can only exchange energy and an isolated is one that can't exchange either matter or energy.

Samira 2B

Is this difference between work and heat the same difference between velocity and speed? Why I think of this is because in the textbook it describes the fundamental difference between these two is that when energy is transferred as work, the molecules in the surroundings move in directed directions ...

CHEMISTRY COMMUNITY

Search found 38 matches

Re: Doubling, quadrupling

Re: Electrostatic Attraction

Re: Shortcut

Re: Practice Final 2010

Pre-Equilibrium Approach Methodology

2nd order rxn integration

Friday Lecture

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15.35 homework

Re: 0 order

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14.41b. Homework b

Q of eqn [ENDORSED]

Re: 14.13

14.13

Cell Notation

Cell Potential

Calorimetry

Homework Problem 9.69

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Homework Problem 9.65

Homework Problem 9.17

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Midterm [ENDORSED]

Re: maximum G

Re: maximum G

Re: Lecture notes, free energy graph

Lecture notes, free energy graph

Clausius Inequality

Lecture notes, Boltzmann Eqn [ENDORSED]

8.117 Homework Problem

8.67

Re: Lecture notes , work eqn

Lecture notes , work eqn

8.13

Irreversible vs. Reversible [ENDORSED]

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Work vs. Heat