Mixture separation, impurity removal, identification, common substance impurity removal, separation

1. Acetic acid and ethanol fractionation.

2. Ethyl acetate and acetic acid separation.

Remove the impurities in parentheses:

1. Acetic acid (ethanol) fractionation.

2. Bromobenzene (bromine) If the impurity is bromine, add iron, benzene, and separate.

3. Ethyl acetate (acetic acid) Add saturated sodium carbonate and separate the solution.

4. Nitrobenzene (nitric acid) separating.

5. Ethane (ethylene) is passed into bromine water.

6. Ethanol (water) fractionation.

Identify the following substances.

1. Benzene and toluene.

2. Ethane and ethylene are passed into bromine water or potassium permanganate to see if they fade.

3. Vegetable oil and mineral oil.

4. Silk and rayon burning. Silk will have a special burnt hair smell. (protein-specific) 5, starch and glucose plus turum reagent (silver ammonia) to see if there is a silver mirror reaction.

6. Sulfur dioxide and ethylene are introduced into bromine water.

7. Add water to benzene and carbon tetrachloride. Benzene density "water, carbon tetrachloride" water.

8. Acetic acid and ethanol were added with sodium, and the hydrogen reaction rate was observed.

9. Sucrose and maltose (not necessarily right) are hydrolyzed by adding dilute sulfuric acid, according to the amount of silver mirror reaction.

1. Acetic acid and ethanol fractionation - boiling point is different.

2. Ethyl acetate and acetic acid separating - immiscible.

Remove the impurities in parentheses:

1. Acetic acid (ethanol) fractionation-boiling point is different.

2. Bromobenzene (bromine) If the impurity is bromine, add iron, benzene, and separate. - Iron bromide is produced insoluble in bromobenzene and partially forms bromobenzene in the reaction with benzene, which is a separator for the reaction of insoluble bromobenzene.

3. Ethyl acetate (acetic acid) is added to saturated sodium carbonate, and the separating liquid - the acid becomes sodium acetate insoluble ester and is pulled with the separating solution.

4. Nitrobenzene (nitric acid) separating - Nitrobenzene is insoluble in water but nitric acid can, so separating the liquid.

5. Ethane (ethylene) passes into bromine water - Bromine water can absorb those ethylene.

6. Ethanol (water) fractionation - the boiling point is different.

Identify the following substances.

1. Benzene and toluene add bromine water, toluene can react with bromine water, benzene is too strong to reflect, methyl is a large bond becomes not strong, becomes reactable with bromine water.

2. Ethane and ethylene are passed into bromine water or potassium permanganate to see if they fade.

3. Vegetable oil and mineral oil - However, it is vegetable oil that fades from Xiushui, which should be unsaturated vegetable oil with unsaturated bonds that can be added with bromine water.

4. Silk and rayon burning. Silk will have a special burnt hair smell. (protein-specific characteristic phenomenon).

5. Starch and glucose add turum reagent (silver ammonia) to see if there is a silver mirror reaction, glucose has an aldehyde group and starch has no aldehyde group to have a silver mirror reaction.

6. Sulfur dioxide and ethylene pass through the magenta solution respectively, and sulfur dioxide can not be magenta fading ethylene.

7. Add water to benzene and carbon tetrachloride. The density of benzene is smaller than that of water in the upper layer, and carbon tetrachloride is the opposite.

8. Acetic acid and ethanol are added with sodium, and the reaction rate of hydrogen is observed, and the reaction between Na and acetic acid is faster.

9. Sucrose and maltose plus turum reagent (silver ammonia) to see if there is a silver mirror reaction, maltose has an aldehyde group and sucrose has no aldehyde group to occur a silver mirror reaction.

Filtration can separate caverns from mixtures of solids and liquids. If two solids are separated, one is soluble in a solvent and the other is insoluble, the method of dissolving first and then filtering should be used. If you want to separate liquid-to-liquid mixtures, you can choose to use the method of dispensing.

Filtration: Separation of insoluble solids from liquids, such as purified drinking water;

Dissolution and filtration: separation of two solids, one can be soluble in a solvent, the other is insoluble, such as separating the silver salt and sand of the bridge jujube;

Centrifugal separation: separation of insoluble solids from liquids, such as separation of mud and water;

Crystallization method: separation of dissolved solutes from solution, such as extraction of table salt from seawater;

Separation: Separation of two miscible liquids that are not sensitive, such as separating oil and water;

Extraction: Add appropriate solvents to dissolve and separate a component in the mixture, such as heptane to extract iodine in aqueous solution;

Distillation: separation of solvents and non-volatile solutes from solution, e.g. pure water from seawater;

Fractionation: the separation of two liquids that are miscible with large differences in boiling points, such as the refining of oxygen and nitrogen and petroleum from liquid air;

Sublimation: Separation of two solids, only one of which can be sublimated, such as separating iodine and sand;

Adsorption: Removal of gaseous or solid impurities in mixtures, such as the removal of colored impurities in brown sugar with activated carbon.

Solid-liquid separation – filtration.

Liquid-liquid separation: two liquids are insoluble, use separating.

The two liquids are miscible but have different melting points and can be distilled.

Solid-solid separation: If one is soluble, it can be dissolved first and then separated.

You can learn and summarize while learning in your daily study, and you will definitely gain something.

1) Add excess iron powder, filter, and the reaction is: Fe

cuso4cu

feso42) dissolves the mixture into hot water to obtain a saturated solution, and then cools the saturated solution and filters it, that is, it has to be served to the kno3 crystals.

3) Dissolve the mixture into "saturated salt water" and filter it to obtain pure sodium chloride crystals.

4) Dissolve the mixture in water, filter (remove manganese dioxide as it is insoluble in water), and then evaporate the filtrate to obtain potassium chloride.

Crystal. 5) The mixture is dissolved in water, filtered, and the obtained solid is washed and dried to obtain pure silver chloride.

(1) Add excess iron powder, filter, and the reaction is: Fe + CuSo4 = Cu + FeSo4

2) Dissolve the mixture into hot water to obtain a saturated solution, and then cool this saturated solution and filter it to obtain Kno3 crystals.

3) Dissolve the mixture into "saturated salt water" and filter it to obtain pure sodium chloride crystals.

4) The mixture is dissolved in water, filtered (manganese dioxide is removed as it is insoluble in water), and the filtrate is evaporated to obtain potassium chloride.

Crystal. (5) The mixture is dissolved in water, filtered, and the obtained solid is washed and dried to obtain pure silver chloride.

Not b: insoluble in dilute sulfuric acid, copper oxide dissolved carbon filtered out.

C: Burns are converted into carbon dioxide with oxygen and carbon monoxide.

d: Add sodium hydroxide to produce magnesium hydroxide precipitate filtration, and then evaporate the solution to dry to obtain sodium chloride.

(1) Excess iron powder filtration (2) (3) The answer has already been given.

4) Add water to dissolve and filter the clear (5) Add water to dissolve and filter the insoluble substance.

(1) Add enough iron powder and filter. Fe+Cu2+=Fe2++Cu (2) dissolved and heated concentrated Filtration, crystallization is potassium nitrate (3) Heating and concentration, filtration, sodium chloride in the filtrate, and then recrystallization (4) Add water to dissolve, filter, heat and concentrate, cool crystallization, filter, and the second filtration is potassium chloride.

5) Add water, filter,

Filtration. filtration

The liquid (or gas) in the suspension (or the hot gas containing solid particles) penetrates the medium under the action of pushing force or other external forces, and the solid particles and their substances are intercepted by the filter medium, so that the solid and other substances are separated from the liquid (or gas) Principle: -- A method of separating the liquid from the insoluble solid by using the difference in the solubility of the substance. For example, a small amount of sediment in crude salt is removed by filtration Experimental instruments -- funnels, beakers, glass rods, iron frames, filter paper.

The essentials of operation should be --- "one stick, two low, and three dependent". (See photo).

One sticker. That is, the filter paper fits snugly to the inner wall of the funnel.

Two low. 1.The edge of the filter paper is lower than the edge of the funnel.

2.The liquid level is lower than the edge of the filter paper.

Three by the eye. 1.The beaker of the mixture is placed next to the glass rod.

2.The lower end of the glass rod is close to the third layer of filter paper.

3.The lower end of the funnel is close to the inner wall of the beaker. [this paragraph] note 1The mixture in the beaker is stirred with a glass rod before filtration and then filtered.

2.If the solution is still turbid after filtration, it should be filtered again until the solution becomes transparent.

3.Washing method of precipitation in the filter: add distilled water to the filter with a flask or dropper to make the water surface cover without sediment, and after the solution is all filtered out, repeat 2 3 times.

4.When doing purification experiments, it is necessary to extinguish the water before it evaporates, otherwise the crystals will be scattered and harm human health.