Reactions Definition and 650 Threads

Homework Statement Determine the forces at the 3 hinges of closed gate with a wind pressure of 700Pa on the gate. Mass of gate = 236kg wind pressure = 700Pa (apllied perpendicularly to the gate) gate dimensions: 4.1m high, 2.45m wide Distacnce from bottom of door to centre of hinges...

It is generally said that reactants react so that they can achieve a lower energy state. Then why does a reversible reaction occur in the first place? If catalysts lower activation energy both ways in a reversible reactions by making the transition state less thermodynamically unfavourable...

Homework Statement I'm having problem of finding the support reactions of Va , Vb and Vc Homework EquationsThe Attempt at a Solution My working is VA +VB +VC = 10+5(3) VA +VB +VC = 25 But , when i sub in the value of VA , VB and VC , it doesn't satisfy the equation of VA +VB +VC =...

Homework Statement A coloured solution, known to contain two metal ions, was treated with excess cold sodium hydroxide solution. When filtered a whitish solid, slowly changing to brown, was retained on the filter paper and a colourless solution collected as the filtrate. Dropwise addition of...

Homework Statement Homework EquationsThe Attempt at a Solution The only thing that helped me was that with excess NaOH, the white precipitate dissolves. The only compounds I know that do this are zinc hydroxide and aluminium hydroxide. However, I don't know how the other reactions will help...

Homework Statement Propose a given synthesis of each of the following compounds starting with 1-butene a) 2-chlorobutane b) 2-methoxybutane c) 2-butanamine d) 2-butene (mixture of cis and trans) e) butane The attempt at a solution I have the structures for 1-butene, as well as each of the...

[Moderator note: Thread moved from technical section, thus no template is shown] Hi everyone! I'm currently learning nuclear physics and I have a question: Watching the binding energy per nucleon curve, is the following reaction energetically favorable? 2H + 4He -> 6Li And why? Thanks!

I'm a little confused by what exactly determines if a reaction is reversible or irreversible. I thought I have heard that if the delta G of a reaction is negative (which means it's spontaneous), that it's then irreversible, but that doesn't make a whole lot of sense when I think about it...

Why is there an excess of foam when I add ice to rum and coke? When I add ice to vodka and sprite/lemonade there is a short burst of foam which quickly dissipates. What causes the reactions to differ? Sugar?

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

Homework Statement Which of the following strong reactions (from a collision) is possible? a. p + p --> p + n + K+ b. p + p --> Λ0 + K0 + p + π+ c. p + p --> p + p + π+ + π- d. p + p --> p + n + π+Homework Equations Conservation of the Baryon Number...

Homework Statement Explain how a cell can use catabolic reactions to drive anabolic reactions, despite energy loss in the form of entropy and heat. Homework Equations Catabolic Pathway: A series of reactions that results in the breakdown of larger,more-complex molcules into small, less complex...

Let us take the example of 89Y(n,n')89mY reaction. In the calculation of Q value we require mass of reactants and products. Both are same here. Then how to calculate the Q value of this reaction or how to calculate the threshold energy of this type of reactions?

1. Homework Statement For part a), I know that it is a nucleophilic addition reaction of CN- to form cynohydrin, but how come there are 2N atoms in E? How does NH4+ react with CH3CHO or the cynohydrin formed? For part b), what reaction is this? Homework EquationsThe Attempt at a Solution

Hi guys, first time poster so play nice :) Outline of problem: The situation I have is that there are 4 supporting columns. These columns support support a wire and this wire is then used to hang wires which support festive lights. (see diagram below) What I'm looking for as an end point is...

Hello all, Assume we have a deuterium-tritium reaction. The energy released is 17.6 MeV. I know from solved examples that neutrons carry 14.1 MeV and Helium carries 3.5 MeV. How do I calculate these numbers (14.1 MeV and 3.5 MeV)?

My grandson asked me this question: If in fact,as Newton said,all actions are accompanied by an equal and opposite reaction, then there can be no single actions in the universe;all actions must therefor be part of a reaction between two opposite and equal actions,which are in fact also...

Ok, this is a large qiestion. Firstly, from second law of thermodynamics, thermal flow always happens between matters kept in different temparature. But while an endothermic reaction takes place, it may extract some heat from environment and consume it. Isnt it against second law? And for...

Hello, I am learning about using Free energy change /delta G to determine if a chemical reaction will occur spontaneously. /delta G = /delta H + T*/delta S. Now, enthalpy change can drive a reaction which leads to a decrease in entropy (multiple reactants => single product). My Question...

Homework Statement Student mix four reagents together, thinking the solutions will neutralize each other. The solutions mixed together are 50.0mL of .1 M HCl, 100mL of .2 M of HNO3, 500mL of .01 M CaOH, 200mL of .1 M RbOH. Did the acids and bases exactly neutralize each other? If not, calculate...

Homework Statement Cl2 and BrCl each react with aqueous KI. (i) Describe what would be seen when Cl2 is bubbled through aqueous KI for several minutes. initially : after several minutes : Homework EquationsThe Attempt at a Solution I thought initially Cl2 would get decolourised, so...

Hi everybody, after studyng a little bit of nuclear physics I have noticed that many reactions (α,β,γ...) end with the new particles in excited states which rea¡main in those for a little time before going to the fundamental. I don't know why this happens instead of going directly to the...

I was confused about this example from a book. After putting in some numbers I got the forces circled in green and blue to be negative. Does this mean the directions for the forces shown is incorrect, and so I should switch the directions before calculating the reaction forces in the bearings (x...

Hi folks, i have to calculate the angular Spin and Parity JP of 17O as a result of the shooting of 16O with Deuterons. So the reaction equation should be: 16O + ²H -> 17O + 1H The only further Information given is that the captured neutron has positive parity and an orbital angular momentum...

Homework Statement The reaction between aluminium powder and anhydrous barium nitrate is used as the propellant in some fireworks. The metal oxides and nitrogen are the only products. Which volume of nitrogen, measured under room conditions, is produced when 0.783 g of anhydrous barium nitrate...

Are there any good models, software or codes that can predict the probabilities of nuclear reactions where an atom of a given type strikes another atom of another type with a given energy? Or is this information only obtainable experimentally? To further clarify, I am interested determining...

Hey guys, I am developing an program for calculation of reactions in a "4 point support beam". The problem is that this structure is Statically indeterminate and hence requires some other method. Support on any level is appreciated, especially from Civil Engineers. I will keep on posting...

Homework Statement [/B] Determine support reactions. a=3 m b=2 m c=3 m F1=20 kN F2=30 kN F3=15 kN M1=30 kN*m M2=25 kN*m M3=25 KN*m q1=12 kN/m q2=24 kN/m Homework EquationsThe Attempt at a Solution

Let's say I'm towing a black hole by using a spaceship, and a rope, and a mass that is attracting the black hole near its event horizon. Let's say the mass unfastens at some moment, and I'm watching everything carefully. Obviously I will notice that the mass has unfastened only after a long...

Homework Statement Determine which is/are redox reaction/s ? ##1. 2HNO_2 + 2HBr \rightarrow 2NO + BR_2 + 2H_2O## ##2. PbO_2 + SO_2 \rightarrow PbO + SO_3## ##3. 2Ag + Cl_2 \rightarrow 2AgCl## ##4. SO_2 + NaOH \rightarrow NaHSO_3## Homework Equations Redox reactions are the ones which involves...

Hi, So I recently got a new job, and when I was being instructed on how to close my department, I noticed that they used quite a bit of chemicals on the same surface (it's a salad bar). I was wondering if any of these chemicals could interact, and if so, what the products would be. First, the...

I'm just wondering if all known coupled reactions are biological, or if there are some that geological and could have preceded the emergence of life on earth. In other words, are there some compounds in geochemistry that are much more abundant than you would expect if the reactions that produce...

Homework Statement Dont really need the answer, but I want to know if point C has Cx and Cy or just Cy. I am confused there.

Hi, I'm reading The Martian by Andy Weir (fantastic book). A character, describing how a Mars mission works, says of fueling their ascent vehicle: "Through a neat set of chemical reactions with the Martian atmosphere, for every kilogram of hydrogen you bring to Mars, you can make thirteen...

Homework Statement Force by uniform loading = 20(5) = 100kN Vertical component of the uniform loading = 20(5)(3/5) = 60kN Horizontal component of the loading = 20(5)(4/5) = 80kN vertical reaction at roller support = Vr vertical reaction at pin support = Vp Homework Equations Fx=0, Fy=0...

There is a liquid phase homogeneous reaction going on in an CSTR, which operates at 4 atm. Is it necessary to have pressure relief valve? If so, what will be vent out when the pressure exceeds, since it contains liquid only?

I performed column cromatography on an oil, and used carbon boiling chips but got some weird IR. I used hexanes and acetone as solvents, I am trying to figure out some of the spikes, soo I am thinking that maybe the boiling stone being carbon could acted as activated carbon and absorbed some...

Hi! I noticed that almost all of the [Compound + Compound = Compound] reactions that I have encountered do not involve any transfer of electrons, or are not oxidation-reduction (redox) reactions. Can it be generalized that all [Compound + Compound = Compound] reactions are not redox reactions...

Homework Statement [C2O4]-2 ------> CO2 Find if the reaction is oxidation or reduction and determine the no. of electrons lost or gained by carbon. Homework EquationsThe Attempt at a Solution I started with finding the oxidation states of both elements. It's 3+ and 2- for carbon and...

In high school chemistry, which I am in right now, we are the very simple means by which to balance a chemical reaction and determine the products of a reactions. My question is; is any reaction possible as long as the valence electrons of the reactants equal eight? Obviously the answer is no...

Dear PF Forum, In previous thread, I am asking about fusion power. But there is one thing that intriguing me. This is one of the reactions that produces tritium. n + _3^6Li -> _2^4He + _1^3H + 4.8 Mev What is this reaction called? 1. Fusion? If yes, why it's called fusion? 2. Fission? 3. Other...

Hello, kind of focusing on the hydration of ethene/ ethylene, but how to liquid catalyst work if the reactants are gaseous? Does the acid catalyst also need to be gaseous if it is to work correctly?

Homework Statement Write down the reactions in which ClO2 is created from KClO3 and H2SO4 Homework Equations KClO3 + H2C2O4 + H2SO4 = ClO2 + CO2 + K2SO4 + H2O The Attempt at a Solution I've attempted and have written down several reacions, or. attempted to, but the part that I find...

Homework Statement Determine the oxidizing agent, reducing agent, element oxidized, element reduced, # of electrons lost per atom, and # of electrons gained per atom. State if the reaction is not redox. 3FeCl2(aq) ------> 2FeCl3(aq) + Fe(s) Homework EquationsThe Attempt at a Solution...

Hello everyone, Sorry I didn't have the time to rewrite the question, Can you help me with this?

Hi Guys, I'm solving this for almost a week, this is a part of our probset in chemical kinetics: The thermal decomposition of dimethyl ether: CH3OCH3 ---K1--> CH3' + OCH3' CH3' + CH3OCH3 ---K2--> CH4 + CH2OCH3' CH2OCH3' + --k3---> CH3' + HCHO CH3' + CH2OCH3' ---k4--> C2H5OCH3 using steady-state...

The rate law is given by R=k[A]^m[ B]^n where m,n needn't be equal to stoichiometric coefficients...but we use r=k[A]^a[ B]^b where a,b are stoichiometric coefficients when we use ratio rate of forward to rate of backward reaction in getting value of equilibrium constant K for any given reaction...

I'm currently reviewing for a final tomorrow, I need to score a B on the final to stay in school. I'm beginning to panic as I've reviewed all day and have gotten nowhere. 1. Homework Statement The tension in the cable AB is 800 lb. Determine the reactions at the fixed support C. The Attempt...

Hi, I'm looking for the reaction that produces the largest temperature drop/absorbs the most energy from its surroundings. It needs to be some kind of dissolution process of a salt being mixed with liquid water. I've looked around on the internet, and it seems tricky to search for, and I don't...

Do we have to rote memorize it or is there mechanism so that we can learn it easily? There are some ion exchange reactions which are simple like NaCl + H2O-------> NaOH+ HCl. but for example what about this? P4 + NaOH + H2O----> ?