Reactions Definition and 650 Threads

I have this problem for my reactor design course and I need some help wrapping my head around it. We have to design a plug flow reactor (PFR), which can be modeled as five equal volume CSTR's in series. The PFR has an inlet volumetric flow rate of ##q_{in}## which contains species ##A_i, i =...

If the catalyst is not part of the reaction and loses no chemical energy, where does it get the energy to speed up the reaction?

This isn't really my area (I'm a mechanical engineering graduate), but I thought maybe somebody on the forum could give me feedback or help redirect my thinking if this is not right. So, neutrinos are famous for not really doing anything, just kind of being there (by this I mean being the...

Homework Statement Two smooth balls of radius 10[cm] and weight 6[kg] are inside a tube of radius 16[cm] that's on the table. what are the reactions from the walls and what is the minimum mass of the tube to be in equilibrium Homework Equations Disassembling of forces using trigonometry The...

When you get the equation for the Gibbs free energy, why do you multiply -T? Can't you multiply just T? I thought about this and came up with an answer of my own, which goes like 'Because its Gibbs 'Free' Energy, when you have that free energy ( \Delta G >0) you have the energy to do...

Rotational Mechanics... Hinges and Normal Reactions -- Please help Could anyone please explain me the reason for two normal reactions on a hinge attached to a door. Also if there are two hinges the direction of the horizontal component of normal reaction is opposite to the direction of the...

Homework Statement Write an equation showing how benzoic acid would react with phenylmagnesium bromide. Homework EquationsThe Attempt at a Solution I am not quite sure where to start first with this Reaction. I haven't seen a Organometallic + acid reaction before. I realize that i have an...

Based on the very basic understanding on enzymes I have gained from Year 12 Biology and Chemistry, I don't undesrtand why the enzymes specific shape also helps the reverse reaction. I guess my trouble would be due to the simplified diagrams I've seen from Biology, where only the forward reaction...

This was one of the alchemists' big quests, and it is evident that it is impossible with the methods that they had available. But how feasible is it to do that with nuclear reactions? Especially nuclear reactions that start with relatively common materials, like hydrogen or carbon or silicon or...

Homework Statement Write the balanced chemical reactions in ionic and neutral forms for: i) Enargite leaching by sodium bisulfide in basic solution to form chalcocite and thioarsenate. ii) Oxygen pressure oxidation of As2S5 in acid solution to form scorodite. Assume all sulfide sulfur forms...

Member ABC is supported by a pin and bracket at C and by an inextensible cable of length L  7.8 m that is attached at A and B and passes over a frictionless pulley at D. Assuming P  450 N and   35 and neglecting the mass of ABC and the radius of the pulley, simplify the problem as much as...

1. What is the expected major product arising from the reaction of 2-ethylbut-1-ene with bromine in carbon tetrachloride? a. 1-bromo-2-ethylbutane b. 2-bromo-2-ethylbutane c. 1,2-dibromo-2-ethylbutane d. 1,1-dibromo-2-ethylbutane e. 1,1,2-tribromo-2-ethylbutane Attempt: For this one I'm...

Say I have a reaction like the one described below [(NH3)5CoCl]^(2+) + [OH]^(1-) <-----> [(NH3)4Co(NH2)Cl]^(1+) + H2O The Keq will be equal to [products(without H2O)] / [reactants]. Now when I add water to this reaction mixture, the reaction will move to the...

After reading this article, Water Vapor Found on Neptune-size Alien Planet - http://www.space.com/27251-water-found-neptune-size-exoplanet.html, I was wondering what other reactions would occur within the atmosphere of the planet as a result of the combination of oxygen at 25% to the 90% volume...

For a reaction like HCl + H2O → Cl- + H3O+, why is this reaction heavily favoured to the right in water? I've heard explanations that the products on the right are stabilized by the polar water molecules (considering aqueous solution). I'm just struggling to fully understand this because the...

Homework Statement A pendulum consists of a disk of mass M1, and a slender rod of M2 (which happens to be 0kg),. Determine the components of reaction that the pin O, exerts on the rod just as it passes the horizontal postion, at which time its angular velocity is ω. Know we know M1 =...

Hello, I have been working on a very interesting problem out of Fogler's Chemical Reaction Engineering. I have completed the problem (parts (a) through (c) which is what i'll do because I've been working on this problem for a while and I'm too tired to do part (d) right now), but I want to...

(Question) Complete and balance each of the following molecular equations (in aqueous solution); include phase labels. Then, for each, write the net ionic equation. (A) NH3 + HNO3 -> (Attempt) I thought that the acid HNO3 would just give it's hydrogen to NH3 and make the resulting reaction...

There is such subclass of capacitors with name ''pseudocapacitors'' which seem to use ''fast faradaic reactions''. This type offers very high capacitance up to 7514 F/g, but relatively low voltage. http://www.nature.com/srep/2013/131018/srep02986/full/srep02986.html What is faradaic reactions...

Homework Statement Hi everyone! I'm struggling to understand how to solve this problem, I searched on the web, but I didn't find anything similar. I have a motor delivering a power P=5kW at n=1500rpm. This motor is mounted on 4 supports, each having a rigidity k=15kN/m. I know that distance...

Hello all, In chemistry class we recently began the subject of nuclear chemistry. I'm sure you all know that nuclear chemistry unleashes a swarm of new particles. My teacher mentioned the Positron, a particle few of my classmates recognized. To help us understand its nature we were told to...

Draw the shear and moment diagrams for the beam in the figure. Clearly show all values, including the maximum shear and maximum moment and their positions on the diagrams. Assume the supports at A and C are rollers and D is a pin support. note there is a hinge at point B. I am having trouble...

Homework Statement Which of the following reactions is likely more exothermic? 1) Vaporized sodium metal reacts with diatomic chlorine gas to form one mole of solid sodium chloride. 2) Solid sodium metal reacts with diatomic chlorine gas to form one mole of solid sodium chloride...

Why are precipitation reactions are irreversible as NaCl + AgNO3 --------> AgCl + NaNO3

Homework Statement Which of the following does not spontaneously reduce 1 M hydronium ion? Homework Equations Spontaneous reduction: + E-zero value. The Attempt at a Solution The answer is 1 M NaOH. However, sodium is a very strong reducer. Why doesn't this reaction go...

Does heat affect the rate of an exothermic reaction?? In my point of view it shouldn't affect it since exothermic reactions are spontaneous so it already works as fast as it can.

I apologise since I already have a question on this board, but I've been stuck for a good few hours understanding exactly how this has been done. The differential cross section for a direct reaction from \alpha to \beta is given by \frac{d\sigma}{d\Omega} = f(k,k')|T_{\beta \alpha}|^2...

Why are precipitate and gas evolution reactions irreversible ( why don't the products react once again ) ??

I'm slightly confused as to how we discuss centre of mass frames in nuclear reactions. We have the reaction a(A,B)b. Before the reaction we can transfer to the centre of mass frame v_c = \frac{\sum m_i v_i}{\sum m_i} and note that the total energy before the reaction is E_{CM} =...

At a high altitude camp in the Rockies, water boils at 95.4°C instead of 100.0°C. A visitor has requested a soft-boiled egg (usually boiled for 3.00 minutes at 100.0°C). The activation energy for the reaction in question is 453 kJ/mol. 6 marks egg protein (l) egg protein (s) How long will it...

Given an aqueous solution (I'm omitting the subscripts): ## NH_3 + H_2O ←→ NH_4^+ + OH^- K_b ##Then we can also say: ## NH_3 + H^+ ←→ NH_4^+ K_b ## as well since they're equivalent reactions, right? They both have the same Kb value as a result, right? So then, ## K_b = \frac...

Homework Statement Hi, I am having trouble with the following problem and I can't seem to find any examples: I am trying to determine reactions at points A and D of the redundant structure below using the unit load method, there is a 10kN load at the top left point (B), all lengths are...

I got a bit of a question that needs answering. See, I'm still not understanding how basic selectivity in organic chemistry works. I'm not looking to know the mechanism or anything. Just one simple thing. I'll give the description given from some textbook first: Homework Statement The...

Homework Statement What would be the products of the following reactions? (a) Phenylmercuric Chloride and phenylmagnesium chloride (b) bromo methyl bis(triethylphosphine)palladium and dimethyl aluminum bromide (c) dimethyl thallium fluoride and difluoro methyl boron (d) bromo methyl...

I had two griffin beakers with 200mL of used photo fix solution on magnetic stirrers ready for electrolysis only to find the power supply was not up to snuff. The backup plan was a redox reaction of Fe with Ag in solution and figure the difference of weight from the set of griffon beakers...

$$C_{5}H_{12} + O_{2} → ... $$ What would be the product? Please show in steps how you're getting your answer, and what oxidation state you're using for C, I don't understand why Carbon and Hydrogen are bonded in this ratio, please explain. Also, please provide any advice/strategies on...

1) Problem Statement 2) Relevant Equations3) Attempt at Solution For question d, I realize in this case that the substance that is oxidized and reduced is the same molecule : iodine. How do I proceed then as the next step would ask for you to find the change in oxidation numbers and multiplying...

Why are the reactions from two objects not at equilibrium ?

First one: is this an intramolecular [2+2] photocycloaddition? And this one: I'm fairly confused about this one. Could it be an intramolecular Alder-ene reaction? Whats confusing me most is that cyclopropyl ring up there. I know they're pretty unstable and I read that they open during...

So when you have a cyclic diene like cyclopentadiene, you can get either the endo or exo isomer. Secondary orbital interactions make the reaction selective towards the endo isomer. This makes sense if your dieneophile is say maleic anhydride: in that case the dienophile has C=O bonds which...

The partial pressures of O2 and H2 in the atmosphere above water are typically very low indeed, so why is it we don't see the equilibria 2 H2O = O2 (g) + 4H+ + 4e- and 2 H+ + 2e- = H2 (g) occurring whenever we have a beaker of water (if this was observed then the H+ concentration would be...

In high school, we calculated the reaction-energy by equating the mass difference and the energy difference with proportionality factor c². How does Einstein's theory of relativity suddenly enter nuclear physics? It startles me because both fields developped historically completely divergent...

So from the first law for a closed system, dU=dQ-dW=dQ-PdV From the second law, dS=dQ/T + Sgenerated (i.e. the entropy generated) Putting expression of dQ from second law into first law, dU=T*dS-T*Sgen-PdV If s and v are constant, dU= -T*Sgen>0 Hence dU<0 This is a...

I'm having trouble understanding the following reactions we did in lab and I am not sure our data is very good. CuSO4 + NaOH yields a blue precipitate. Which I understand is Cu(OH)2. I get this. Next we add NH3 to the solution above and nothing obvious changes. I think the precipitate...

I understand the concept of balancing chemical equations but in the case of redox reactions I don't understand the physical meaning of balancing in acid medium and balancing in Basic medium. Sure, I know how to balance the equation but I want to know what it means physically. Why do we need to...

Homework Statement A 100-kg uniform rectangular plate is supported in the position shown by hinges A and B and by cable DCE that passes over a frictionless hook at C. Assuming that the tension is the same in both parts of the cable, determine (a) the tension in the cable, (b) the reactions at...

I have trouble identifying what moments and forces are due to a support http://postimg.org/image/a2xux5qjx/ Can someone explain the moments and forces (and their directions) due to the support in this picture? http://postimg.org/image/kto0b0ft3/ Why isn't there a MAx and Ax due to the...

I couldn't find the answer to this anywhere so I figured I'd make a thread. Can exothermic/endothermic reactions occur in a vacuum? Or if there are no surroundings, then what would the transfer of heat be? Thanks.

Homework Statement http://postimg.org/image/60w1pznz9/ Are the forces at A the same for members ADE and member ABC? Likewise, are the forces at D the same for members FDB and ADE?

Hello I'm not sure if this belongs in this forum or the homework forum, but I have a quick question about selectivity and yield in reactions where one product is made, and that product returns to one of the reactants to create another separate reaction. for example: C_{6}H_{12} + H_{2}O...