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Anonymous users2024-02-07Inorganic chemistry is associated with common inorganic reagents, easy to identify water according to the color of common metal ions, remember the steps of special experiments, such as aluminum dissolved in NaOH, thermite experiments, special catalysts, industrial electrolysis NaCl impurity removal steps and reasons are organic experiments all kinds of organic substances and water, benzene, gasoline specific gravity dissolution relationship, when solving the problem, you have a number in mind, bold conjecture and use, do more questions, try to cultivate your own ideas, innovation questions are basically no problem.
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Anonymous users2024-02-06Removal of impurities is the removal of impurities, and separation is the separation of two substances, which are different in nature and use different methods.
Separation, which means to separate, to leave, to separate, to separate. It can be used for the separation of feelings between characters and objects.
From a scientific point of view, separation is the process of using the differences in the physical or chemical properties of each component in a mixture to assign each component to different spatial regions or to the same spatial region at different times through appropriate devices or methods.
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Anonymous users2024-02-051.Dissolution filtration method: one substance is easily soluble in water, and the other substance is insoluble in water, you can dissolve the mixture of these two substances in water, and then filter, you can separate these two substances.
2.Cooling heat saturated solution method: according to the solubility of the two substances in water there is a large difference.
A mixture of these two substances is formulated into a mixed solution, and then the less soluble substance crystallizes and precipitates the temperature suddenly, so that the two substances are separated.
3.Substance dissolution characteristic method (extraction method): In the mixture of two substances, one substance is not tolerant of organic solvents, and the other substance is easily soluble in organic solvents, and neither of these substances reacts with organic solvents, according to this characteristic, one of the substances is dissolved in this organic solvent first, resulting in the phenomenon of stratification, and then they are separated.
4.Gas precipitation method: In a mixture of two substances, one substance can react with other substances to produce precipitation or gas, while the other substance does not.
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Anonymous users2024-02-041.Saturated sodium chloride solution.
2.Saturated sodium sulfite.
3.All passed.
NaOH solution, which is represented below by the equation:
so2+2naoh
na2so3
h2oso3+
2naoh=na2so4
H2O so that both sulfur dioxide and sulfur trioxide are fixed.
NaOH solution, and then add dilute sulfuric acid, will react sulfur dioxide, Na2SO4 will not react. In this way, the sulphur trioxide is removed. Just collect the sulphur dioxide and you're done.
4.Adding an excess of sodium hydroxide solution to aluminum oxide will react with sodium hydroxide and will not react with magnesium oxide.
al2o32naoh
2naalo2
h2onaalo2
It is called sodium metaaluminate.
Soluble and water) after the reaction is fully and completely, filter the solution, wash the magnesium oxide with water several times and finally dry it to obtain pure magnesium oxide.
5.Excess CO2 gas can be introduced.
na2co3+co2+h20---2nahco3
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Anonymous users2024-02-031.Add hydrochloric acid (HCl) until no bubbles are generated;
na2co3+2hcl=2nacl+h2o+co2
2.Excess iron powder is added, Fe can be replaced with Cu, and then filtered.
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Anonymous users2024-02-02There are filtration, separation, extraction, distillation.
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Anonymous users2024-02-011.Add an appropriate amount of HCl and filter.
2..Add excess iron powder and filter.
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Anonymous users2024-01-31Impurity removal method. 1..n
o—Burning copper wire. 2cu+o
2cuohs) — with a full closure of the slipper and. nahco
Solution. nahco
hs=nahs+h
O+Coco)—scorching copper oxide.
cuo+co=cu+co
HCl) — saturated. nahco
Solution. nahco
hcl=nacl+h
o+cos(hcl)
Saturate. nahs
Solution. nahs+hcl=nacl+h
shcl) — saturated. nahso
Solution. nahso
hcl=nacl+h
O+SOHCL)—with saturated saline, HCl
Soluble. cl
Insoluble. Toner.
The mixture is ignited in oxygen. c+o
CO is passed through the scorching calcium oxide.
c+cao=ca+co
Condition. High temperature.
Passes in scorching iron oxide.
3c+2fe
o3co 4fe
Toner (MNO
Concentrate hydrochloric acid. mno
4HCl (concentrated. =mncl
Cl2ho - add dilute hydrochloric acid to dismantle.
cuo+2hcl=cuclho
Ofeo Method 1:
The solid mixture is dissolved in excess sodium hydroxide solution, and the iron oxide is removed by filtration, leaving the filtrate. alo
2oh2alo+ho
Excessive amount of sedan potato is introduced into the filtrate. co
Filtered get. al(oh)
Heat to make. al(oh)
Decompose. alo
2ho+co
al(oh)
hco2al(oh)
=alo3ho Method 2:
Will. Solid. Body. Mix. Combine. Thing.
Dissolve. In. Pass. Measure.
Target. Salt. Sour. Dissolve.
Liquid. Middle. Be. Mix.
Combine. Thing. Finish. Whole.
Dissolve. Untie. al
o6h2al
3ho feo
6h+=2fe
3HO 2 added to the overdose.
Naoh dissolve.
Physics is actually very easy to learn, and the content of compulsory 1 and compulsory 2 is not very connected, so don't have a sense of fear first. This, it is definitely very important to listen to the class in class, even if the teacher does not speak well, but he is the teacher after all, he understands the content of this part, so he must listen to the class. Before class, it is best to preview, it is best to look at the content, and then try to understand the knowledge points, generally speaking, a piece of content is a knowledge point, the most important preview method is the next step, to try to do a sample problem in the book, whether the answer is correct or not, do it to know how the topic related to this place will come out (the general question is to change the soup but not the medicine). >>>More
This is a commonly used method of separation and impurity removal: >>>More
1.First, an excess of BACL2 was added to remove the sulfate ions in K2SO4, then an excess of potassium carbonate was added to remove the excess barium chloride and calcium chloride, then an excess of potassium hydroxide was added to remove the magnesium chloride, and finally dilute hydrochloric acid was added to remove the excess potassium carbonate and potassium hydroxide. >>>More
Do more practice, and practice writing more equations in chemistry.
I'm a high school student, and I'm almost 4 months later on the college entrance examination, I'm not good at physics, I'm tackling this now, if you want to say how physics can get on, then I tell you that only when you fully or most of the understanding of physics scenarios, then I think physics is not very difficult for you, but it depends on how you understand, as for chemistry, I think you should consolidate the basics, especially the chemical equations in the books, my teacher said the same, remember not to engage in sea tactics so that only make the brain become rigidNumbness! I hope you make some progress and get the good results you hope for, don't be too suspicious of whether you can pass the test, be happy!