Why do reactions take place

Create a free Team What is Teams? Learn more. Why do disproportionation reactions take place? Ask Question. Asked 3 years, 8 months ago. Active 1 year, 7 months ago. Viewed 1k times. Improve this question. Bhargav Saikia Bhargav Saikia 39 3 3 bronze badges.

I had my thesis printed 6 copies and binded within 45 minutes. Show 5 more comments. Active Oldest Votes. Improve this answer. If I understand you correctly, you mean that there are significant number of routes for, say, Glucose to two molecules of pyruvic acid by the combinatorial complexity.

The step size of each route is various. That's why almost all complex chemical reaction takes more than one step. Is my understanding correct? To get, say, 25 atoms in the correct arrangement would require a colossal decrease in entropy. Individual steps lowers the entropic penalty, allowing reactions to take place. Making things worse: The machine needs to be made of Lego parts, too.

Add a comment. Collision Theory Gasses This is especially relevant in gasses, but I will relate it to glycolysis later. Hope this helps! Shady Puck Shady Puck 4 4 silver badges 13 13 bronze badges. Yes, there are a lot of things that could form if many atoms collided at once, but the bigger issue is that it becomes astronomically more unlikely to get 3, 4, Even a very intricately designed enzyme would have little change of producing benzene from 6 carbon and 6 hydrogen atoms, it simply requires too much coordination.

For example 2,3-BPG is "only" an intermedate in glycolysis, but it has vital functions on its own. Reason behind the glycolysis process The reason why this process is as it is, is efficiency towards reaching the goal.

Energy in the body Before I continue, you need to understand a bit about Gibbs free energy. Back to glycolysis With this background information in mind, we can explain the reason behind the complex glucolysis process better. Is there anything preventing 6 hydrogens atoms fusing into a carbon atom?

Is there anything preventing U into splitting into 20 different atoms in a single step? You need multiple steps to go from hydrogen to carbon… To the second: No, nothing prevents this. Mathijs H Mathijs H 61 1 1 bronze badge. WaterMolecule WaterMolecule 3 3 silver badges 10 10 bronze badges. Lux Claridge Lux Claridge 2 2 bronze badges. Will it get best answer? No, the previous answers definitely fit the bill better.

However, it does explain why there isn't one singular reaction and provides some context to help the OP with rest of biochem. It could explain in more detail how unnecessary complexity would evolve, though. Sign up or log in Sign up using Google. Sign up using Facebook. Sign up using Email and Password. Post as a guest Name. Email Required, but never shown. Featured on Meta. Now live: A fully responsive profile.

Version labels for answers. In a chemical reaction, reactant A does not simply transform into product B. Reactions take place through what we call transition states. Transition states are intermediate structures between reactants and products of a chemical reaction step. They are usually higher in energy less stable than both the reactants and the products, and the energy difference between the reactants and the transition states, also known as activation energy, is the barrier necessary to overcome for a thermodynamically-favorable reaction to take place.

See below a now complete version of the free-energy diagram of the Sn2 substitution reaction. As you can see, the process is thermodynamically favorable, but a barrier or activation energy of The larger the activation energy, the lower the speed or rate of a reaction at any given temperature. Easy enough to remember. This allows us to make a clarification between stability and inertness as properties of chemicals.

Stability is a thermodynamic concept, while inertness is a kinetic concept. A compound can be both unstable and inert. That is why we can handle and store thermodynamically unstable primary alkenes such as 1-propene without them isomerizing to more-stable secondary alkenes such as cis- or tran spropene see the first two schemes.

But we can trick kinetics! Catalysts can be used to lower the activation energy of chemical transformations, allowing them to proceed more rapidly, or simply to proceed at all!

Now that we know why chemicals react, let me explain how we chemists try to override the system and make activation barriers lower. A catalyst is a chemical entity a molecule, a salt, a coordination complex… which speeds up a chemical reaction.

It also can unlock new reactivity pathways and make reactions work that would not be possible otherwise. The electrophilic aromatic substitution of benzene with molecular bromine Br—Br. This reaction is traditionally carried out using a Lewis acid as catalyst, such as iron tribromide.

But let us imagine first a catalyst-free version of the process, which I am certain can occur if you mix together benzene and bromine, and heat it up enough. The first step of this reaction is the formation of the well-known Wheland intermediate. An intermediate not to be confused with a transition state , which rather connects intermediates together is a reactive chemical species which is formed in one of the steps in the middle of a chemical reaction of A leading to B, as intermediate point.

For benzene to be transformed into bromobenzene, it has to pass through this intermediate species. Intermediates can rarely be isolated, since they usually are both thermodynamically unstable and kinetically reactive. By adding a catalyst to the mixture, we can access new transitions states, which are more stable, and hence lower in energy.

And what happens when the transition state of the rate-limiting step of a reaction is lower in energy? That the activation barrier of the whole process is much lower! This is basically the role of FeBr 3 the catalyst of this reaction: stabilizes transition states and intermediates. Also, note that FeBr 3 is recovered unreacted with the products. Therefore causing you to act differently or different chemical reactions to take place that aren't good for you.

Most of the chemical reactions takes place in cytoplasm however some specific reactions do take place inside nucleus. Most chemical reactions within a cell could not take place without a compound. Chemical reactions take place inside the cell is a fluid called cytoplasm. Through such reactions, organisms can metabolize among other cell activities. All chemical reactions in living things take place in what kind of solution.

Log in. See Answer. Best Answer. Chemical reactions also occur in one of two circumstances: a the reaction is following a fundamental law of nature enthalpy-its the nature of things to want to use the smallest amount of energy possible, so when a reaction can occur that produces more energy, it will. Also, entropy-its the nature of things to be as disorganized as possible, such as the breaking down or decomposing of material b something forces the reaction this one is self-explanitory.

Study guides. Q: Why do chemical reactions take place? Write your answer Related questions. Where to all the chemical reactions take place in a cell? Do chemical reactions take place in the membrane?