Metathesis Reactions- Predicting the Products of Precipitation Reactions Metathesis reactions or exchange reactions are reactions in which the products are formed by the exchange of the ions present in the two reactants. Consider the following reaction as an example: In the products, however, the magnesium ion and the sodium ion have exchanged "partners" anions.
At first I felt bad for not understanding this. From the journal Neuropsychoanalysis which based on its name I predict is a center of expertise in not understanding things: There was a lot of mathematical knowledge in the room: I met with a Princeton physicist, a Stanford neurophysiologist, a Cold Springs Harbor neurobiologist to discuss the paper.
Again blanks, one and all. But almost all the most interesting neuroscience of the past decade involves this guy in one way or another. I continue to hope some science journalist takes up the mantle of explaining this comprehensively.
First, free energy is a specific mathematical term in certain Bayesian equations. But actually using Bayes on all this data quickly gets computationally intractable.
Under this interpretation, Friston is claiming that the brain uses this Bayes-approximation algorithm.
This sounds in line with standard predictive processing theories. Under this interpretation, the brain implements predictive processing through free energy minimization. This comes from the same source as above. It also ends up equivalent-ish to all those other things like trying to be correct in your understanding of the world, and to standard predictive processing.
Third, free energy minimization is a claim that the fundamental psychological drive is the reduction of uncertainty. I get this claim from the Alius interview, where Friston says: If you subscribe to the premise that that creatures like you and me act to minimize their expected free energy, then we act to reduce expected surprise or, more simply, resolve uncertainty.
Because this action has epistemic affordance; in other words, it resolves uncertainty expected free energy. This simple argument generalizes to our inferences about hidden or latent states of the world — and the contingencies that underwrite those states of affairs.
The discovery that the only human motive is uncertainty-reduction might come as a surprise to humans who feel motivated by things like money, power, sex, friendship, or altruism. But the neuroscientist I talked to about this says I am not misinterpreting the interview.
The claim really is that uncertainty-reduction is the only game in town. In a sense, it must be true that there is only one human motivation. Then the only weird thing about the free energy formulation is identifying the common currency with uncertainty-minimization, which is some specific thing that already has another meaning.
On the one hand, there is a lot of basic neuroscience research that suggests something like this is going on. The basic idea seems to go roughly as follows.
There are two ways of bringing Q in alignment with my sensory input: Compared to the present state, the sensory input will then have lower surprise. So any transition to these states can be seen as a reduction of free energy, in the unambitious sense of the term. This is clearly nuts.
There are at least two fundamental problems with the simple picture just outlined. One is that it makes little sense without postulating an independent source of goals or desires.
Where does the hallucination come from? Otherwise it would be a miraculous coincidence that I mostly hallucinate pleasant and fitness-increasing states. Some further part of my cognitive architecture must trigger the hallucinations that cause me to act.
The second problem is that efficient action requires keeping track of both the actual state and the goal state.
Recall that minimizing free energy can be seen as an approximate method for bringing one probability function Q close to another function P. How would that work? This might lead to an interesting empirical model of how actions are generated. I said it comes about by approximately?
Why do I want to reach out for the pizza?A conventional balanced equation with integer-only coefficients is derived by multiplying each coefficient by 2: 2C 2 H 6 +7O 2 6H 2 O+4CO 2 Finally with regard to balanced equations, recall that convention dictates use of the smallestwhole-number.
Metathesis reactions not only take place among ionic compounds, they occur among other compounds such as Sigma Bond Metathesis and Olifin Metathesis. Metathesis reaction is a type of chemical reactions, which include combination, decomposition, and displacement.
Metathesis Reaction ® A reaction where the cations and anions exchange partners: AX + BY ® AY + BX. Metathesis reactions are driven by the formation of a product, and can be divided into three different categories according to the type of product that is formed.
1. Formation of a Precipitate The net ionic equation is: Ag +. A salt metathesis reaction (from the Greek μετάθεσις, "transposition"), sometimes called a double replacement reaction or double displacement reaction, is a chemical process involving the exchange of bonds between two reacting chemical species, which results in the creation of products with similar or identical bonding affiliations.
! 81!! Balanced+chemical+equations.+! Abalanced-chemical-equation!isarepresentationofa!chemical!reaction! using!the!chemical!formulas!ofthereactants!and!products. In order to write a net ionic equation, remove the spectator ions from the complete ionic equation.
The spectator ions are the free ions that are unchanged in the reaction, so they appear on both sides of the complete ionic equation.