Reaction Definition and 1000 Threads

One that occurs immediatly?

Dear all, As we know, the reaction rate can be calculated as following: R = N * σ * Φ (1) Where R is reaction rate (events/s/cm3) σ is cross section (cm2) Φ is flux of incident particle beam (particles/s/cm2 N is density of target (atoms/cm3) Logically, there is a limitation of R, because...

Homework Statement Hello all, I am doing this lab http://scc.scdsb.edu.on.ca/Students/onlinecourses/Sikora/sch4u/v12/60.pdf i am stuck on trying to find hte concentration of ch3cooh Homework Equations n = m / M and c = n*vand i think the ideal gas law could be used but not sure The Attempt...

Homework Statement Consider the decomposition of N2O5: 1. N2O5 → NO2 + NO3 2. NO2 + NO3 → NO2 + O2 + NO 3. NO + N2O5 → 3NO2 a) Find the reaction for the decomposition of N2O5 to stable products b) Find the steady-state concentration of the intermediate(s) c) Use the previous to show how the...

Hi everyone! I know that the Election Day thread has now been locked by the moderators, but I felt I had to respond to Donald Trump winning the 2016 US Presidential Election. I had a swirl of emotions floating inside of me, from shock (despite knowing that there was a reasonable chance that...

Homework Statement Homework EquationsThe Attempt at a Solution Can't find this exact reaction mechanism online. Help? http://imgur.com/a/X9P7e I don't know what the mild oxidation does. Does it split the double bond into a ketone and aldehyde?

i.If all the calcium carbonate used in set up X was used up for the reaction, what is the amount of moles of carbon dioxide produced during the reaction ? (Ca = 40, C = 12, O = 16) My progress: Molar mass of CaCO3=(40+12+(16*3))gmol-1=100 gmol-1 Molar mass of CO2=12 + 16* 2 gmol-1=44 gmol-1...

Homework Statement A control rod to limit the rate at which a nuclear reactor is working is made from boron which is sealed in a casing. A boron atom (105B) is able to capture a neutron; an atom of lithium (Li) and an alpha particle being produced in the process. As a result helium gas is...

Hey, I have a simple ANSYS model shown in link: https://dl.dropboxusercontent.com/u/104865119/hand_calc.PNG . Ansys reaction force in z axis is +121 N and -121 N. Can someone clarify how do you get to this result using hand calculations?

In my textbook, i have read about unimolecular elimination and nucleophilic unimolecular substitution reaction of organic compounds. In those reactions, firstly one bond breaks automatically then as soon as a carbocation forms then a nucleophile attacks the carbocation to complete the reaction...

Homework Statement Organic life is based on complex organic molecules formed from smaller ones during a long evolution. Using data in Appendix 2, investigate one such reaction: 2 C2H6 (g) → C4H10 (g) + H2 (g) (a) Calculate ∆rH and ∆rS for such a reaction under standard conditions (Po = 1 bar...

Homework Statement I'm asked to find the VA and VB in this question . Homework EquationsThe Attempt at a Solution Here's my working : VA +VB =1000(6) =5000+0.5(400x3) VA +VB = 11600 total moment about A = 0 , sum of moment about A = 5000(6) -9000 + (4000/2)(9 +3(2/3) ) -VB(9) =0 hence VB...

Does reaction force only occur when it is in contact with another object? And also if rollercoaster goes around in a circle, at the maxium height, why isn't there any reaction force (got this from a book). Personally, I think that rollercoaser have clamps attached between the path and the...

I have been reading many examples of control volume calculations regarding nozzles They all end up with a reaction force on the nozzle in the direction of the flow. I can't understand this from a Conservation of momentum perspective. I would expect that the reaction force, by Newtons third...

Homework Statement A plank of length 2L leans against a wall. It starts to slip downward without friction. Show that the top of the plank loses contact with the wall when it is at two-thirds of its initial height. (from Kleppner&Kolenkow,An Introduction to Mechanics 1st ed., problem 6.41)...

Its a very simple question . So when the carboxylic acid radical -COOH is standalone in an aliphatic molecule without any other acid or basic radicals Pka would be around 4.5 . But when something like -NH3+ is present in the same molecule the Pka for -COOH changes , even though -NH3+ wouldn't...

Homework Statement 2. The attempt at a solution Let rightward acceleration of the block (A+B) be $$a$$. Let downward acceleration of block (A) be $$a'$$ down. For block A: $$mg-T=ma'$$ $$N+ma=0$$ For block B: $$T+N=Ma$$ On solving $$N=-\dfrac{m^2g}{M+2m}$$ by taking $$a=a'$$.But...

I was doing a science experiment involving enzymes and hydrogen peroxide, and by adding heat to the catalase, it should have sped up the reaction, but instead it slowed it down. Is there a reason why this happened?? Isn't heat supposed to speed up the reaction, instead of slowing it?

Homework Statement Can someone please help me with this A level physics question on Mechanics. Help will be appreciated. The picture of question is attached. :D Thank you Homework EquationsThe Attempt at a Solution [/B]sin20x590=201.79N or cos70x590=201.79N

My books says Thermite reaction is an exothermic reaction, it release large amount of heat so that temperature increases upto 3500°C On the other hand it is written Melting point of diamond is 3500°C So my question is whether diamond can by melted in such reaction?

Homework Statement The diagram shows a section of a curtain track in a vertical plane. The curved section, CDE, forms a circular arc of radius of curvature 0.75 m and the point D is 0.25 m higher than B. A ball-bearing of mass 0.060 kg is released from A, which is 0.50 m higher than B. Assume...

Homework Statement There is a object traveling at 0,2m/s with a mass of 75,000kg. The object impacts a fixed point at a distance of 3.5m from its center of gravity (COG) and rotates around this point. What is the reaction force at the point of rotation? Homework Equations I think it is...

Homework Statement A particle is attached by means of a light inextensible string to a point 0.4 m above a smooth horizontal table. The particle moves on the table in a circle of radius 0.3 m with angular velocity ω. Find the reaction on the particle in terms of ω. Hence find the maximum...

Only particles that possesses enough energy to overcome the activation energy and orientated correctly will collide and form products. How about those particles which do not possesses enough kinetic energy to overcome the activation barrier? Does it mean that for a particular chemical reaction...

We can react one mole of ##CH_4## and one mole of ##Br_2## to obtain the following equation: ## CH_4 + Br_2 \rightarrow CH_3 Br + HBr ## A single bromine atom switches places with a single hydrogen atom. Now, if we supply a greater amount of ##Br_2## while keeping the amount of ##CH_4## the...

I'm having trouble understand a passage in our book. The author claims that the reaction ##^2H+^2H \to ^4He + \gamma## is unlikely since the ##Q## value is large (##23.8## MeV) which happens to be greater than both the neutron and proton separation energies. This seem very counter intuitive...

Hi everyone, I'm an engineer student, so I'm not an expert in nuclear reactions and subatomic physics, but I had a little thought experiment and I was wondering if there were any reachable subnuclear threshold to improve energy production. Let's suppose a spherical (with IO) container of...

Homework Statement Felder & Rousseau 4.73 (p. 184) A mixture of propane and butane is burned with pure oxygen. The combustion products contain 47.4 mole % H2O. After all of the water is removed from the products, the residual gas contains 69.4 mole% CO2 and the balance is O2. What is the mole...

Hi ! I study nuclear reactions due to electron beam. In simulation (GEANT4), I note, whatever incident energy (10 MeV < E < 1 GeV), the primary electron is not absorbed and continues after the interaction. This is not the case for protonuclear, photonuclear or neutronuclear reaction...! What...

Contrary to potential appearance, this is not homework. I've been out of college for a long time now. Just working on a project with my kids and I'm trying to approach specific energy of these reduction reactions from the theoretical side, mostly so I know what sort of safety precautions to...

"As you sit in your chair and study your physics (presuming that you do), the force of gravity acts downward upon your body. The reaction force to the force of the Earth pulling you downward is the force of your body pulling the Earth upwards". I read this somewhere just a bit ago and it's...

What happens to the normal reaction of the force of gravity on a body orbiting around the Earth? The force of gravity provides the centripetal force, but does all of it get converted to centripetal force? Is there any kind of resultant force towards the centre of the Earth (due to the normal...

According to textbook, elementary reactions have an order of reaction equal to the summation of the stoichiometric coefficients. why is this so? And there is another problem, we can balance an equation in different ways and get different stoichiometric coefficient sets, for rates, which set is...

Homework Statement Write an expression for Kc for the following at equilibrium; CaCO3(s) + CO2(g) + H2O(l) ⇔ Ca2+(aq) + 2HCO3-(aq) Homework Equations K = [products]^(coefficients)/[products]^(coefficients) The Attempt at a Solution I know that pure solid and liquid substances should be set...

Homework Statement Homework EquationsThe Attempt at a Solution Negative ∆H means that the product is more stable. Change from solid to gas requires energy so cancel out A and C. Reaction D doesn't make sense. The products of reaction B and E are more stable than the reactant because there is...

EDIT: I figured out what I'm stuck on is WHY do nuclear reactions favor the a reaction such that the product has a HIGHER binding energy per nucleon? Also how is energy released in a fusion reaction if the product requires more binding energy per nucleon? I need an explanation... "The graph...

Hi! I got a question. I have been given the reaction of the equation and no other data. I have to calculate the mass percentage of H2CO3. The gas dissolves in water. 1. Homework Statement CaCO3 + H2SO4 = CaSO4 + H2O(l) + CO2(g) Homework EquationsThe Attempt at a Solution CaCO3 + H2SO4 = CaSO4...

Homework Statement Hi I need to solve the next problem: a car with a total mass of 1950KG hits a speed bump at 19,4m/s. The speed bump is 0,05m high and has a angle of 45°. The car hits the bump with the front axle first. How much force acts on the front axle on the moment of impact. Homework...

Hi there: I'm trying to balance a reaction in which methane is oxidized by citric acid in solution. Both methane and citric acid will be transformed into carbon dioxide. To begin, I checked that the reaction is indeed a redox reaction. C6H8O7→CO2 So, I calculated the oxidation number for...

Let me start this question with a quote: "In the reaction turbine, the rotor blades themselves are arranged to form convergent nozzles. This type of turbine makes use of the reaction force produced as the steam accelerates through the nozzles formed by the rotor. Steam is directed onto the...

A mixture consisting of KCI and MgCl2 weights 1.2505 g. The mixture was dissolved in water and an excess of AgNO3 was added. The chloride ions were precipitated as AgCl. The mass of AgCl obtained was 2.5788 g. Calculate the percentages of KCI and MgCl2 in the original mixture.

This is the question and the answer, the problem is i don't know how to get to the answer top is question and bottom is answer I attempted to divide the gas concentration by 24 to get molar mass, but that didn't work and how am i suppose to know that OH- is one of the products? i guessed...

What is the conceptual meaning of "reaction orders greater than 1 reactions conversion increases in given time as concentration increases?

There is reaction between PhCHO + SF4 I tried to make the mechanism but I stuck .

What is in pea nuts that causes such violent illness and even death?

Dear PF Forum, I have a problem with calculating energy which I should have learned long ago in my high school time. If I push (accelerate) a 1 kg object 1 meter/sec2 for 10 seconds, I spend energy like this. Distance = 1/2 at2. So I would have pushed this object for 50 metres. So I'm using...

Hi, I need to size a CSTR for the transesterification of tri-glycerides into methyl esters (bio-diesel) by reaction with methanol and NaOH catalyst. The transesterification reaction taken place in 3 reversible steps: TG + CH3OH <--> DG + ME DG + CH3OH <--> MG + ME MG + CH3OH <--> C3H8O3 + ME...

Homework Statement At 1500 ° C , CO is formed more than at 1000 ° C. Is the reaction from left to right exothermic or endothermic? Homework Equations C(s) + H2O ↔CO(g) + H2[/B]The Attempt at a Solution I think its Exothermic reaction . The temperature is increased from 1000°C to 1500 °C . If...

1. Homework Statement Homework Equations KE = 3/2 R/NA T The Attempt at a Solution By using the formula above, I used 2.4 x 10^-14 J as the mean translational KE , but it should be 1.2x10^-14 , why? I thought the mixture contains both deuterium nucleus and the proton? Why half KE of mixture?

Homework Statement Homework Equations ΣF=0 The Attempt at a Solution Basically I don't agree with this solution, I think it is R1 + R2 - mgcos5 + mv^2sin5/r = 0. Can you help me please? thanks!