Standard Definition and 1000 Threads

Homework Statement The standard free energy of activation of a reaction A is 83.7 kJ/mol at 298K. Reaction B is 10 million times faster at the same temperature. The products of each reaction are 10 kJ/mol more stable than the reactants. (a) What is the standard free energy of activation of...

Homework Statement I am stuck on the last problem. Homework Equations Just the error propagation equations The Attempt at a Solution I initially used the multiplication error propagation formula. So the average force would be the impulse divided by the time, the same thing as the impulse...

What's the simplest, most direct way to derive the lagrangian of the SM? I saw earlier today: L[S M] = L[Dirac] + L[mass] + L[Gauge] + L[Gauge/psi] That seems like a good starting point. I like it because it says the SM Lagrangian is simply the sum of four lagrangians. The next step...

Which of the following do you prefer as possible solution to the cosmological constant problem or why QFT computes vacuum energy density that is 120 magnitude more than from observational data? Sometimes I think the metric (1.a) needs to change, but on other days I think QFT needs to change...

I mainly just need some clarification here. I was doing my homework and then browsing the web to find an answer to my problem and came across mathewarehouse' definition of Standard form and then I looked at my homework and went..."huh?" I don't understand if my homework is listening this wrong...

Type Ia Supernova are generally thought to be white dwarfs that, either by accretion of mass from a companion (single degenerate), or as a result of a merger with a white dwarf companion (double degenerate), approach and then exceed 99% of the Chandrasekhar limit of about 1.44 M☉, at which point...

My book denotes by σ:Δk→X for some suitable topological space X a standard k-simplex of X. It then describes the free abelian group generated by such σ's as the group of k-chains on X. It is not clear to me what is meant by a chain for a map σ. I understand a chain in Rn to be sums of integer...

The question asks to solve for delta S surroundings at 298K when 2.49 moles of H2S (g) react. reaction: 2H2S (g) + 3O2 (g)= 2H2O (g) + 2SO2 (g) My problem is that I don't know how to calculate delta S surroundings. So to solve the problem I'm making the assumption that -Delta S surroundings =...

I have just started reading about them, so forgive my basic question. I wonder how a "standard" wave propagating on a string whose end has been moved and brought back to its initial position is different from a soliton. Or is it indeed a solitary wave? I ask because when studying waves before...

I read in a magazine (namely Scientific American) that the Standard Model successfully combines Quantum Mechanics with General Relativity, but I also remember reading in The Elegant Universe that the Standard Model fails to do so. What's true and what's not?

Write the equation for an ellipse with vertices (0,-3) and (0,3), minor axis of length 10. I know that the standard form of an ellipse is (x-h)^2/a^2 + (y-k)^2/b^2=1 Please help me ! Please! Thank you so much for your time, I appreciate it.

I'm trying to understand the derivation of the expression for the random Brownian force on a particle in a medium with coefficient of viscosity η. It turns out it is gaussian over some timescale, with a standard deviation that depends on the temperature and the viscosity. I'd like to read a...

Homework Statement "Consider a standard uniform density. The mean for this density is .5 and the variance is 1 / 12. You sample 1,000 sample means where each sample mean is comprised of 100 observations. You take the standard deviation of the 1,000 sample means. About what number would you...

I was recently checking out a paper about gravitational energy and found a unexpected minor inconsistency when I did the calculation entirely in isotropic coordinates. I later tracked down what caused it, and it surprised me a bit, so I'm wondering if others were aware of this. Basically, I'd...

substances in their elemental state have enthalpies of formation equal to zero,why?

A voltaic cell is composed with reactants and products in their standard states.So when it operates,the concentration of all substance must change,it should no be hold.Am i right?

Hi, I've read on the cern website that the standard model does not predict that matter inherently has mass, if this is the case how does the model predict particle masses and also why doesn't it predict that matter inherently has mass? Thanks.

I am looking all over and can't find the standard for the welding pipe with fittings into '4-'12 pipe array, by standard i mean the welding type, pipe\fitting preparation and any other Info\tips that can help.

Given a one-dimensional Gaussian distribution, distributed as following: f (x) = exp (-x ^ 2 / (2q)) / q / √ (2pi) proof which q is the standard deviation Thanks !The standard deviation is defined by: http://www.mathsisfun.com/data/standard-deviation-formulas.html

I did the problem but none of my answers match up with the answer choices so I'm obviously doing it wrong. Can someone show me how to do these two problems. I have a test coming up and I am so behind For women aged 18-24, the systolic blood pressure (in hg mm) are normally distributed with a...

Homework Statement Calculate ##(4.3 \times 10^8)+(2.5 \times 10^7)## Give your answer in standard form The total marks for the question is 2 Homework EquationsThe Attempt at a Solution The answer is ##4.55 \times 10^8## because that's what my calculator gave. That will score me one mark. I am...

Homework Statement Hi, I am doing some basic X-ray analysis and trying to quantify the measurement uncertainty associated with my determined value for the K-α line of copper. I have obtained the x-ray spectrum from a copper target using a detector and multichannel analyzer (No. of pulses/pulse...

Hi, I want to know the enthalpy of formation of Ga2O3 and Ga2O at low pressure (ultra high vacuum) and high temperature. Temperature seems easy, but I'm not sure how to get the enthalpy values for low pressures. Does anyone know if there are books with enthalpy - pressure diagrams of these...

The following is a list of various quantities (molar enthalpy changes) found in a typical Chemistry course: Atomization Enthalpy Formation Enthalpy Combustion Enthalpy Neutralization Enthalpy Solution Enthalpy Hydration Enthalpy Ionization Energy Electron Affinity Lattice Energy Bond Energy...

I was thinking about this and either I have a misunderstanding of black holes or they are simply not how the standard model proposes them to be. Lets start out by setting a few a statements from the standard model that you agree with. If you disagree about any of these points please comment so...

Say if I have a sample space 2,3, and 5. I want to find by what percent points deviate from the mean. So I would take the standard deviation as follows. 2+3+5 / 3 = 3.33 (2-3.33)^2 + (3-3.33)^2 + (5-3.33)^2 / 3 = 1.55 (1.55)^(1/2) = 0.775 So we get a standard deviation of 0.775. So how do I...

I am reading An Introduction to Rings and Modules With K-Theory in View by A.J. Berrick and M.E. Keating (B&K). In Chapter2: Direct Sums and Short Exact Sequences in Section 2.1.16 B&K deal with the standard free right R-module on a set X. I need some help with the meaning of B&K's terminology...

I have taken over a project halfway through (which is never an easy thing), and I need to get a threaded insert to place inside a steel piece that a threaded rod will move through. The original person working on the project wanted to get Acme threading on the inside of the insert and standard...

I am reading An Introduction to Rings and Modules With K-Theory in View by A.J. Berrick and M.E. Keating (B&K). In Chapter2: Direct Sums and Short Exact Sequences in Sections 2.1.11 and 2.1.12 B&K deal with infinite direct products and infinite direct sums (external and internal). In Section...

Homework Statement How does skew and range affect the standard deviation; does one affect it more than the other? Homework Equations None The Attempt at a Solution It seems as though if the range increases, the standard deviation increases because the SD is a measure of how spread apart...

hi (Wave) know its a big jump from calc 3 down to stats but i can't remember how to get the standard deviation. I am given this table and I am asked to find the standard deviation. can i please get a step by step solution? thanks (Blush)

Homework Statement The standard enthalpy of formation of the metallocene bis(benzene) chromium was measured in a calorimeter. It was found for the reaction Cr(C_6H_6)_2(s) --> Cr(s) + 2(C_6H_6)(g) that \Delta_r U~at~583 K = +8.0 kJ/mol . Find the corresponding reaction enthalpy and estimate...

Homework Statement There are 55 independent normal observations with mean 100. The first 50 observations have variance 76.4 and last five have variance 127. Calculate the probability that ##\bar{x}=\frac{1}{55}\sum_{i=1}^{55} X_i## is between 98 and 103. Homework Equations The Attempt at a...

I need to prove that $$std(x+c) = std(x)$$ I have been trying to use the properties of the mean such as $$mean(x+c) = mean(x) + c$$ I am confused on the following property of the mean, is this statement correct? $$\sum\limits_{i=1}^{i=N}(x_i - mean(\{x\}))^2 = mean(\{x\}) \\$$ If that is...

I was looking at this old chart (before the standard model was completed) and this thing with Kaon notations was confusing. So I understand that the top right number on a particle denotes charge, but what is subscript? Does that denote the number, as in which exact particle it refers to? Because...

Also, how would you do $\int \sqrt{x^2-4}$? $$d(x^2-4)^{3/2}=3x\sqrt{x^2-4} \,dx$$ $$\int \frac{\sqrt{x^2-4}}{3x}d(x^2-4)^{3/2}$$ Not sure how partial integration will be useful here. What standard integrals do you see?

Why is it such a big deal? According to the "modern" (Wilsonian) viewpoint, non-renormalizability is not such a "sickness" of a quantum field theory, as long as one adopts the viewpoint that the theory is not UV complete, aka, the theory is simply an effective field theory with a finite cut-off...

Hi, I am trying to solve the chemical equilibria in a kraft mill bleach plant to predict mineral scale deposits. I am using the van't Hoff equation to account for temperature dependence of the formation constants, but I need the enthalpy of reaction for all equilibria and I am missing some...

Hello, Is there a common word in the standard math vocab list (postulate, axiom, lemma, corollary, proposition, theorem, definition, claim, remark, etc.) for something that will be treated as a postulate for convenience, even though it is known to be provable from previous postulates and...

I foolishly skipped most of my analogue electronics classes, and inevitably failed the exam. I'm now trying to revise for the resit but I'm so far behind that I just cannot understand any of the lecture slides, and I'm getting very stressed. The part of the module I am revising at the moment...

Definition/Summary This article is a list of standard integrals, i.e. the integrals which are commonly used while evaluating problems and as such, are taken for granted. This is a reference article, and can be used to look up the various integrals which might help while solving problems...

Hi, I'm looking for a standard (CGA, ANSI, ISI, etc.) which lays out requirements for the marking of pressure ratings on shut off valves (which aren't cylinder valves) in the USA. Does anyone know what it is or if it even exists? Any insights are much appreciated. Thanks! Blake J

Let's say a student does a simple experiment where she conducts 10 trials at each x value (at each value of the independent variable). She collects data over 30 x values, giving her 300 total trials. For each of the 30 x values, she averages the 10 y values and she calculates the standard...

My A level Chemistry textbook defines Lattice Energy as "the enthalpy change when 1 mole of an ionic compound is formed from its gaseous ions under standard conditions"; a definition which I can't fully grasp because of the "standard conditions" part. How can gaseous ions exist under standard...

Dear Fellows, If we fit our data to a quadratic equation then What is meant by standard error for linear and quaratic coefficients ? I know that standard error is the standard deviation from the Sampling data. But for individual coefficients what is its interpretation ? Best Wishes Masood

I've worked in calibration for a few years and I know that my equipment has to be calibrated by a standard that is a certain amount more accurate than the piece of equipment I'm calibrating, but where exactly does it end where the most accurate piece of equipment is calibrated by the absolute...

In the standard model gravitron is a particle but Higgs boson is not. The Higgs field causes particles to acquire mass. Mass generates a gravitation field. Is gravitron is in any way related to Higgs boson? Is the Higgs field any way related to gravitation field?

my question is on part ii, my range ( as shown in the photo), is between 4.52 and 16.28, so my working would be (6+10+4+4)/(6+10+4+4+1) X100% ... the answer given is 72% which is differnt form my answer? which part of my working is wrong ?

I am presented a review of data which gives: vapour pressures of a liquid have been measured and fit to the following equation: Log10 (mmHg) = -3571/T + 8.999 The melting point has been determined to be 392.7 K. A Cp value given for the liquid is 250 J/mol K and the ΔSvap is 117 J/mol K...

Hi. I've been reading that if one places a Dp brane in a 10d space then it's possible to have a string with [11] Chan-Paton index i.e. a string that starts and ends on the same Dp brane. Since the separation of the brane with itself is 0, this string corresponds to a massless particle. Why is...