Reactions Definition and 650 Threads

TL;DR Summary: When is arrow-pushing useless? I tried a lot of time to explain 2 KMnO4 + 3 H2O2 → 2 MnO2 + 2 KOH + 2 H2O + 3 O2. My work: $$\mathrm{MnO}_4+\mathrm{H}_2 \mathrm{O}_2->\mathrm{MnO}_3+\mathrm{H}_2 \mathrm{O}+\mathrm{O}_{2}^{2-}-$$ $$\mathrm{MnO}_4->\mathrm{MnO}_2+\mathrm{O}_2$$...

Is there a way to trace all the reactions I have had to others' posts in various threads of this forum? Like an index? If only to retrieve all the useful information I've learned from them, but have forgotten already now where it was located. Also, I thought OP meant online participant, but...

I'm having problem in drawing the distributed load (weight per foot) for the inclined beam as it shows. should it be rectangular? if so shouldn't the distributed load be vertical down as the resultant weight at the centroid (W) please help me understand how to draw the free body diagram for this...

The figure is shown below: Here is my FBD for the figure with assign +x and +y directions I started off by summing up the forces in the x-direction: Next is the summing up of the forces in the y-direction: After this, I solved for the moment at point A: assuming that counter-clockwise is +...

Hey! I am currently working on a project where I have to react copper (II) chloride dihydrate (dissolved in water) and aluminum. When writing the equation and the ionic equation for this, would you include the dihydrate in the formula since it’s dissolved in water and no longer in its...

The problem comes with solutions. However, I dont get the 3 steps in the solutions. Why do they calculate decay for 120min in step 3? And why is only the daughter nuclide relevant and no granddaughter? There might be something lacking in my knowledge about nuclear reactions. Also, I don't know...

I would be interested in calculating the constraint reactions on the 6 pads in yellow in the figure, about 300mm apart among them and loaded with F=12500 kN in blue. Since the system is highly hyperstatic, I don't know how to calculate the constraints. Can you give me a hand? I've made a FEM...

Hi, I was reading about fusion reactions recently, and it was pointed out that the problem seems to be that positively charged nuclei repel each other. If that is the problem, why don't scientists try to go with another fusion reaction? Would it be possible to have fusion if neutrons fuse...

One of the alternatives was NaBr My resolution was as follows: NaBr + HCl forms NaCl and HBr I researched and saw that HBr would be a gas and would be denser than air because its molar mass is greater. However, the answer was not that. My error is in which step? In the reaction? What would...

Hi everyone! There is a task that I can't solve. Can you explain me how I have to draw the full mechanism? Draw the mechanism of the reactions of step 1 and 2. Indicate the product before step 3. (in step 2 also TMG =Tetramethylguanidine is given and instead of the protecting group DMT was...

Figure: My attempt at a solution: We know that ##Q=A_T## We calculate ##Q##: $$Q=\dfrac{3\cdot 480}{2}+\dfrac{600\cdot 6}{2}+600\cdot 2=3720\, \textrm{lb}$$ Then we look for the point ##\overline{x}## of the centre of gravity: $$\overline{x_1}=1\, \textrm{ft},\quad...

This started out with interest on antiproton radiotherapy but as it turns out there's little to no publication on the reaction equations that's happening. So this is just an attempt to have some equations at hand. The reactions are for antiproton with water. For simplicity everything is...

When the US first developed nuclear weapons against the Nazis and Japan, their primary concern was whether the nuclear reactions can trigger the atmospheric nitrogen to fuse and burn the whole atmosphere. However this claim was instantly debunked by physicists. Their reasoning is that in order...

hello i have a question about kinetics : to have the integrated rate law for second order reaction the professor write the following why we don't write the rate like this : rate = -1/2(d[1]/dt) ? why we ignore the stoichiometric coefficient ?

we assume that we have an exergonic reaction , a substrate going to a product , is the negative ΔG′° the principal reason that the equilibrium favors the product (there is more product than substrate at equilibrium )?, or it is not and that depends on other factors? , thanks .

What happens to the higgs field when say a fusion reaction occurs. Like if mass is converted into energy and the higgs field gives a particle mass what happens to higgs field. I doubt this, but is the higgs field the mechanism that converts mass into gamma rays. Go easy on me I only have a high...

Considering a ferris wheel with the spokes being pretensioned cables. Which directions do the loads vs reactions go?

I am trying to understand redox reactions. I have read, and learned about oxidation numbers and even viewed examples of balancing redox equations. However, nowhere have I seen an explanation of why I care about redox equations. In contrast, I understand that a chemical equation must be balanced...

So, for the link "AB"...they didn't directly list the pin reactions from pin "A" here, but I want to be sure that I understand what those reactions are. So, from what I see in this image, the member is pushing at the pin "A" (red arrow) because otherwise, the bucket would want to rotate...

In chemical reactions generally ΔG < 0 , but if we were to consider a reversible path between pure reactants and products at 1 bar pressure , shouldn't the ΔG = 0 for every reaction ? and if it is due to non-pv work , I don't see any non pv work being done in reactions happing in a closed...

Hello! in this good afternoon ;). I need some help for this beam and his support reactions. The problem it is done, but my result its different from the teacher`s result. I'm sure my answer is correct, as even the "SkyCivbeam" online software also gives the same results. it appears that the...

reaction steriochemistry is syn? the product of reaction b is meso?

So far I got the simplified forces of 12, 48 and 36 kN, at 1, 5 and 9.5m (from A) respectively, but I'm confused as what to do next, can you help me?

I am studying the synthesis of FDG for a job interview. The process of creating the F-18 used in FDG involves the collision of O-18 with an accelerated proton -- the proton kicks out a neutron and everything adds up. I am just wondering why a neutron is specifically knocked out, why wouldn't...

The solution for a) is 2H2O+2e- → H2 +2OH-, and the solution for b) is O2, because the half reaction at the anode is 2H2O→O2 +4H+ + 4e-. I don't understand why the electrolysis does not involve Na2SO4 being reduced or oxidized, and only considers water. Thanks.

I am learning about the gamow energy and saw a graph explaining the gamow peak - but i am not quite sure i understand the relationship about the overwall gamow window. From what i think i understand so far for fusion if the gamow energy peak is greater the gamow window becomes smaller is this...

For organic chemistry, what is important to memorize when I am reading a textbook? Should I memorize the structures and names of different organic compounds when they are described as examples? Or is it more important to memorize the organic reactions? Also, does anyone have any tips on how to...

The question: How will the first reaction take place for instance? Is CH3S- the nucleophile? Will it be added to the oxygen and the other hydrogen(H+) get attached to the other oxygen, with the double bond shifting to the center(C2-C3)? If this is right then where will CN- will attack?

If an endothermic reaction has a lower temperature, since the forward reaction rate decreases more, the reaction should produce more energy to compensate for the decreased energy and raise the rate of the forward reaction until it reaches equilibrium with the reverse reaction. Is this saying...

I apologize in advance if this is in the wrong forum, I have no idea where this question would really sit. A number of proposed theoretical weapons, and a concept often used in science fiction, describe a satellite launched, or rather dropped, rod that would gain large amounts of kinetic energy...

Hi, Its my first time here in PF, I was wondering what could be a fast endothermic reaction(with water) that does not burn the skin/ cause severe allergic reactions when/after touching or in contact with the reaction. (With high rate of cooling and hopefully no bubbles or gas forming). E.g to be...

This might be a little unsettling for some and I don't know exactly where to post this but here we go... What would the reaction of say a mother cat be in the moment if you where to take one of it's baby and kill it in front of them? Would they attack you? Would they show some signs of sadness...

Option A is wrong because the reaction is still possible but just can not happen spontaneously? Option B is correct Option C is wrong because it should be binding energy per nucleon Option D is wrong because it should be nuclear reaction instead of chemical reaction? Thanks

Hi I was wondering what equipment is used to measure the actual yield of a chemical reaction when a voltage is applied?Thanks.Adrian

First of all this is a question that I had while reading some concepts of my book, so this isn't a homework question. I have started reading the thermochemistry chapter of my book, and it shows the story of Hess' Law and says that it was created is because a calorimeter can't be used to measure...

Hello everybody! I have a doubt about a reaction. $$ p + n \rightarrow \Lambda + \Sigma^+ $$ I have to establish if it is allowed or not. Charge is conserved (1 -> 1) Baryon number is conserved (2 -> 2) Strangeness is not conserved (0 -> -2) Third component of the isospin is not conserved (0...

Hi, i am new to simulation and for my thesis i have to make a simple simulation by using mcnp4c2. Is anybody familiar with this version of MCNP? I need to calculate the fission reactions per second in a geometry of a spherical sub critical reactor of Uranium with low percentage of U 235 with...

For equilibrium, using ##\Sigma \vec F = 0##, we get ##n_1 + n_2 = 300\; \text{N}##. Taking the system as a whole and applying ##\Sigma \vec \tau = 0## about the hinge (pin) at the top from where the load is hung, we get ##n_1 \times (0.8) \times 4 = n_2 \times (0.6) \times 3##, by taking...

In acid-base reactions, the reaction never goes 100% toward the product, right? A reverse reaction will occur and eventually reaction toward product and reactant will reach equilibrium. In lab/industry conditions where yield is important, how does they push the reaction toward product? I am...

I was stuck with a question; how does enzyme lower the activation energy of a reaction. After several internet searches, I found a post in biostackexchange which partially clarified my question. I'll write my current understanding before I proceed to my actual question. Activation energy is the...

How Dihalogens Catalyze Michael Addition Reactions. - NCBI What Michael Addition is about: https://en.wikipedia.org/wiki/Michael_reaction I do not know what the definition of 'piectron' is. In the abstract of the paper, I assume it is a misspell. Which makes me wonder? I learned about...

132g/ml 870g/mol 2-propanol acetate

Hello! I am taking a course in nuclear physics using the book An Intro to the Physics of Nuclei & Particles by Dunlap. I am a little confused by an explanation related to the critical radius for nuclear reactions. The author first defines a value ##vq## as the average number of neutrons...

Consider a reaction: H2+CuCl2= Cu+2HCl This is a substitution reaction.But is this may not be a reversible reaction since Cu is less active than .So Cu can't substitute H from HCl and make a backward reaction.Is my thinking right?

Well, I know this is not the "Chemistry" subforum but the question is all about quantum physics. When you study the Schrödinger equation you can compute the time evolution of the wave function, see what energy levels are possible etc. You can calculate the spectra of atoms describing them as a...

Directly without any introduction _ I really want some help from chemical engineers I was just looking for some chemical reactions that can make water unstable like when we put it in the water the water will move will not be stable or in an equilibrium state thank you very much

Is it possible to create a surface with immobilised enzymes (or any other technique) that will perform a multistep reaction?

Hello all, I am curious as to whether it is possible to create aluminium from a thermite reaction. Thermite, as standard, uses aluminium and iron oxide, which react together when burnt to create a blob of molten iron. I would like to achieve a similar result, but with a blob of molten...

Cl2(g) + 2I–(aq) -->I2(aq) + 2Cl–(aq) (reaction 1) [2S2O3^(2-)(aq) + I2(aq) --> S4O6(2-)(aq) + 2I–(aq) (reaction 2) Why isn't n(I2)(reaction 2)=2n(S2O3^(2-))(reaction 2). I don't see why this is wrong. <edit: remove size and italics>

Hi, In electro-chemical cells (galvanic, concentration, etc) or more generally when some RedOx reactions occur in solutes, is there always a phase change? I mean is there always a change in the state of matter from liquid to solid or gas?