Reactions Definition and 625 Threads

I am trying to set up some realistic conditions for a game I am designing, and need a bit of help. I am speaking very generally in this context. What are the percentages of mass released as usable energy in a uranium fission reaction, a D-T fusion reaction, and a positron-electron annihilation...

Homework Statement What mass of iron(III) chlorate is needed to precipitate all the chromate ions from 234 mL of a 0.100 M lithium chromate solution. Homework Equations The Attempt at a Solution we just started precipitates and my teacher didnt explain the procedure very well...

Hello, Are all endothermic reaction take their energy from a coupled exothermic reaction? Is it possible that an endothermic reaction would take it's energy from the physical process of cooloing the environment? If so- why are there so many coupled reactions in cell biology if it can just take...

This at first may sound like a question based in chemistry, but I feel it is more of a particle physics question. When a chemical reaction occurs, it can be exothermic or endothermic. It is my understanding that if bonds are formed, energy is released, and when bonds are broken, energy is...

This is a subject I am unfamiliar with, and was just wondering where I should start in order to learn about them and how they affect different elements and form other substances step-by-step. From what I know, an Acid donated a Hydrogen Ion, and a Base takes a Hydrogen Ion, and an Acid has to...

Homework Statement The 400N weight of member AB acts at its midpoint. The length of member AB is 3m. Determine the tension in cable BC and the reactions at A. Homework Equations m=rxf? maybe simple force equations The Attempt at a Solution Not sure whether to use sum of all forces...

Hello chemists! In the classical treatment of reaction kinetics, the overall reaction rate is usually written as a constant times the concentration of species raised to some power (called the order of reaction for that species). It is impressed in high school level students that this reaction...

I know that chemical reactions can emit light and heat, and these are part of the electromagnetic spectrum. But are there any chemical reactions that can directly produce electromagnetic emissions in the radio part of the spectrum?

Do exist some nuclear reactions which are completely safe and produce no radiation whatsoever? And those radioactive materials could be used as convenient energy storage? For example,I know there exist such reaction as electron capture during which electron is captured, but not emitted.You...

Why some of the chemical reactions are slow? Is it directly proportional to the size and shape of the molecules - since the complex shape makes 2 molecules less probable coming in contact with the appropriate alignment for the chemical reaction to happen? I'm trying to find an answer within...

Homework Statement When acid gets on your skin, why must you flush the area with plenty of water rather than neutralizing with a base? Homework Equations The Attempt at a Solution I'm guessing it's because neutralization reactions are exothermic so heat could be released, thus...

Homework Statement What is produced when NH3 is mixed with CuSO4(aq)? What is produced when H2SO4(aq) is mixed with Cu(NH3)4+2? Homework Equations None The Attempt at a Solution For the first one, I'm thinking I should treat ammonia as a Group 1 metal and do a single...

1. Homework Statement Which of the following Nuclear Reactions are allowed? A) e- + p --> \mu- + p B) n --> p + \pi- C) K- + p --> (anti)k0 + n 2. Homework Equations While I don't know if there are any relevant equations, I know that there are several conservation laws that are required...

Homework Statement Is this first or second order rate? Calculate the rate constant and be certain to give its units. A-->products Chart A (mM) / Time 1 / 0 .5 / 11 .25 / 20 .1 /...

"Spontaneous" reactions require activation energy? To my understanding reactions are considered "spontaenous" if they require no additional energy for the reaction to occur. However, they require activation energy. Why is activation energy not considered "additional energy?" The term...

Hi What is the reaction of calcium carbonate and water. I thought it was insoluble but I was looking up some notes from a chemistry practical i did and it says CaCO3(s) + H2O (l) → Ca(OH)2(s) + CO2(g) Can someone please explain this reaction for me as I can't find it on the internet...

Checked google no satifying answer.Thanks :smile:

Homework Statement The question is: The weightless beam, ABCD, shown in Figure below is supported by a pin support at B, and a roller bearing at C. There is a 4 kN/m UDL along the whole beam, as shown. There is an 11.2kNm clockwise couple at A. The vertical reactions of B and C...

A friend asked me for an interesting way to destroy a boxful of flashcards for a video scholarship. Being almost the 4th of July, I mentioned making some kind of fireworks out of them, but I want to give him something a little more... safe and legal. I tried looking on Google for chemical...

Hello. Are there any chemical reactions of the Briggs-Rauscher variety that will continue to oscillate indefinitely with continued agitation? B-R fades out after a few minutes of agitation, and I am curious as to whether there are oscillating reactions that will continue to oscillate as long as...

combustion/explosion reactions - anyone have an explanation? I am a layperson, desperately seeking enlightenment! I have been thinking about combustion/explosion reactions and have been trying to build a mental model of the physical processes involved. I can imagine two atoms, let's say...

Homework Statement [PLAIN]http://img571.imageshack.us/img571/4411/statics.jpg A Man weighing 180lb has climbed 60% of the ladder shown. The ladder weighs 30 lb. Find the forces the wall & floor resists (reactions). The angle the ladder makes with the floor is 60 degrees. Homework Equations...

When solving for reactions in a 2D diagram as seen below, how does each type of joint affect the summation of forces in the x & y components? My problem asks to find the summation of forces in the x & y components, and has a smooth pin connection in the left of the beam and roller on the right...

hello, I would like to know if following reactions are possible/correct and under what condition: 2NaOH+K->KOH+NaOH and HCN+K->KCN+H Theoretically it should be possible but I'm not sure,Please help me understand Thanks

Does it matter which way I have the solutions? i.e. is this correct (in a reaction between iron and magnesium): Fe2+ | Fe || Mg | Mg 2+ Or is this correct: Fe | Fe2+ || Mg 2+ | Mg Or are they all correct, as long as I have them on the correct sides of the salt bridge?

[b]1. Fe2+ + MnO4- -> Fe3+ + Mn2+ (acidic solution) 2. I need to write a half reaction for the oxidation and reduction process and I am totally lost. If I could have help on this one, maybe I will understand how to complete the balance of my work.

Lots of articles and papers I read talk about the gamma rays produced during fusion reactions. And yet, when I look at equations for fuel cycles, the sum of the energies of the fusion products equals the total energy liberated. Since this implies that all of the energy released in the fusion...

Homework Statement Hi, I'm trying to find out the formulae that gives me the threshold energy for a nuclear reaction (i.e. The minimum amount of energy required to induce a reaction). I've got a question which states an endothermic reaction of : O + p --> F + n has a Q value of...

Homework Statement In chemical reactions, when energy is released, mass is lost according to Einstein’s formula just as it is for nuclear energy (though the amounts lost are so small that for centuries scientists thought that mass was conserved). When a kilogram of coal is burned, it...

Homework Statement V205(s) + U(s) ---> V0 2+(aq) + UO2 2+(aq) *Balance the rxn under acidic conditions. *Balance the rxn under basic conditions.

from masteringphyics.com, ||\\\\\\\\ the binding energy of a nucleus is defined as the difference between the rest energy that the individual particles would have if they were not bound in a nucleus and the rest energy of the nucleus itself. So, stated another way, fusion reactions are...

The reaction between 2KOH + H2SO4 -> K2SO4 + 2H2O is exothermic... However is this reaction spontaneous as well? If so then why? the concentration that i used was: KOH - 2M H2SO4 - 1M (I writting a lab report on the "course of this reaction"...spontaniety of the reaction is a...

i have propkem solving this equations attempt to solve i looke out in http://www.fsj.uAlberta.ca/CHIMIE/chem161/ReactionsofGrignardReagents.html http://cnx.org/content/m15245/latest/ http://www.chemguide.co.uk/organicprops/haloalkanes/grignard.html...

Homework Statement Hi there! I have recently studying how to design gantry. but I got one problem about how to calculate the vertical load on the beam. can anyone help me and let me know how to find the Reactions 114kn and 183kn in the picture. and I know how to find the max bending moment...

I honestly don't know how to approach this problem. I am to find the reactions at C and E. Since E is a roller, it will have moment, but since C is a pin, it won't have moment? What exactly do I need to figure out before attempting to write the equations for the reactions? Do I need to find the...

I am to find the reactions at A. Am I doing this right? Do I also need to find Ax? If I do, would it just be Ax - 400cos30 = 0?

Can a catalyzer in a reaction be an intermediary as well? Im not sure, i don't think because it would have to consume it self...

How does double salt reactions work? Let's say, Cu(NH4)2(SO4)2 + NaOH --> ?? OR maybe Cu(NH4)2(SO4)2 + BaCl2 --> ? Thanks.

Hi there in my knwoledge the energy released in any nuclear reaction is because of the fact that the mass off the reactants is greater than the mass of the products and the missing mass is converted into energy but in a nuclear reaction the bindind energy of the products is greater than that of...

Homework Statement Find the reactions exerted on the members by the supports. Homework Equations Sigma Fx = Net force acting on x-axis = 0 Sigma Fy = Net force acting on y-axis = 0 Sigma M = Net Moments = 0 The Attempt at a Solution 10N/m -> changes to 4N at centre acting...

What will happen if two black holes are coming nearby? what will be the reaction (change in behavior)?

I'm just curious, what was the first reactions to Einstein's theories (it was 1905, right?) ... were they refuted or supported? was it like "Oh! these are nonsense..these are pseudoscience .. we shall burn you"?! or were they garnered respectable amount of debate?... were they supported by...

In neutron activations, target materials are being beamed by high energy flux, thus making the target materials excited and undergo radioactive decay. Neutron analysis then can be performed after the materials are "cool" enough by placing inside the hood with enough shielding. My question is...

Hello, If a reaction is spontaneous when calculated using Gibb's Free Energy formula, Delta G = Delta H - (T*Delta S) Does it mean the reaction will occur at impossible temperatures even (such as 999999999999999999999999 degrees Kelvin) for ex: H2O(g) C(s) --> CO(g)+H2(g) Delta H =...

Homework Statement Homework Equations ΔH rxn = ΔH products - ΔH reactants ΔU = q + w The Attempt at a Solution Pretty overwhelmed with the entire problem. Since the ΔH's of all reactants and products were in the literature for the reference temperature of 298.15 K, I was able to...

Zn---Zn+2 + 2e-

Homework Statement If the following substances were heated what gas would be given off and what solid would remain? strontium carbonate, zinc carbonate, and iron carbonate. Homework Equations N/A The Attempt at a Solution So I presume carbon dioxide would be given off and the 3...

Hi, I know that there are a number of different ways that uranium-235 can decay when a slow neutron collides with it. I am trying to get a picture of all the possible reactions that can occur. One is U-235+n --> Ba-144 + Kr-90 +2n Another is: U-235 +n --> Xe-140 + Sr-94 +2n Can anyone give...

Hi, I just learned about oxidation and reduction reactions and I have some questions. Are all ionic reactions redox reactions? Do elements that make up covalent compounds always have an oxidation number of zero because they only share electrons, not give or take? That is what I was thinking...

Nuclear reactions in which the Q value is negative (endothermic reactions) imply that energy is absorbed in the process of the reaction. Is this to be interpreted as a case where the initial rest mass energy is less than the rest mass energy of the products of the reaction? If affirmative, it...