According to the properties of the substance, the following substances can be identified, and the re

1) Ice and water: different physical properties, states, (ice is solid, water is liquid) 2) Alcohol and white vinegar: physical properties, different smells, (alcohol has a taste of wine, white vinegar has a sour taste) 3) Oxidase and rust: physical properties, different colors.

4) Lime water and purified water: chemical properties, lime water becomes turbid when carbon dioxide is introduced, and there is no change in pure water.

1) Ice and water: different physical properties, states.

2) Alcohol and white vinegar: different physical properties, smell, wine aroma, acetic acid; Chemically, it reacts with magnesium and is vinegar, and if it does not react, it is wine.

3) Magnesium oxide and rust: chemical properties, dissolve with a small amount of acid, colorless and transparent is magnesium oxide, yellow is rust.

4) Lime water and purified water: chemical properties, sodium carbonate is added, the precipitation is lime water, and the dissolution and clarification is pure water.

1) Physical properties, different morphologies (solid, liquid, I don't know what words to express) 2) Chemical properties? The smell is different.

3) Physical properties? The color is different (it's magnesium oxide, right?) ）

4) Chemical, blowing breath (CO2) lime water will become turbid.

Hehe, I've forgotten about these for a long time, and I can't answer so standardly, but I hope it will help you.

1) Ice and water: different morphologies Ice is solid and water is liquid.

2) Alcohol and white vinegar: different tastes, wine and sourness.

3) Oxidase and rust: different colors Rust is iron-red 4) Lime water and purified water: The chemical properties are different, blow air to lime water with a straw, and there will be white precipitate formation

DA is not feasible because phenolphthalein is colorless in both neutral and acidic environments.

b Not feasible, neither CO2 nor N2 supports the burning of wood sticks.

c Not feasible, all are strong acids, all turn red.

d Yes, sodium hydroxide is easily soluble in water, while calcium carbonate is insoluble in water and can therefore be distinguished.

d(a No, phenolphthalein is colorless in neutral acidity; b No, both CO2 and N2 are inert; c No, all acids will turn red; d Yes, sodium hydroxide is soluble in water, while calcium carbonate is insoluble and can be distinguished).

1。OK. Benzene floats on water; Alcohol is miscible with water; Bromobenzene is underwater;

2.。No.

1) NaHCO3 was added dropwise with Ca(OH)2, and the reaction was:

2nahco3 + ca(oh)2 = caco3↓ +na2co3 + 2h2o

Phenomenon: White precipitate is produced immediately after indropping.

2) Ca(OH)2 was added dropwise with NaHCO3, and the reaction was:

nahco3 + ca(oh)2 = caco3↓ +naoh + h2o

Phenomenon: White precipitate is produced immediately after indropping.

Therefore, there is no way to distinguish between the two.

3.OK. Methane burns without black smoke. Acetylene combustion produces a relatively thick black smoke.

So choose B.

, carbon monoxide and carbon dioxide: when the ignition method is adopted, it is carbon monoxide that can be burned, and carbon dioxide can not be burned, and it is feasible to use smell, because both are odorless, so it is impossible to distinguish but carbon monoxide is toxic, and it cannot smell so it is not possible to use the method of smelling wrong

Salt water and water: When the pH measurement method is used, both solutions are neutral, and their pH values are 7, which cannot be distinguished; When evaporating and crystallizing, the solid residue is salt water when evaporated, and the water without obvious traces can be distinguished

Sodium hydroxide and calcium carbonate: when dissolved in water, because sodium hydroxide is dissolved in water, and calcium carbonate is insoluble in water, the original substance that disappears after adding water is sodium hydroxide, and calcium carbonate has no obvious change; When hydrochloric acid is added, both are reflected, but calcium carbonate and hydrochloric acid react and bubbles bubble out, so when hydrochloric acid is added dropwise, the original substance that can produce bubbles is calcium carbonate, and the original substance without bubbles is sodium hydroxide correct

Magnesium strips and aluminum strips: Due to the different metal activities of the two, the ignition phenomenon of the two in the air is also different, magnesium strips burn violently and produce white smoke, while aluminum strips burn but no white smoke is generated but white solids can be identified When hydrochloric acid is added, the most violent reaction is magnesium bars, and the slower ones are aluminum bars Correct

Therefore correct so choose D

1. Add excess NaOH solution, and after producing white precipitate, it is zinc salt, and magnesium salt is insoluble.

Zn(OH)2 + 2 NaOH = Na2[Zn(OH)4]2, add SNCl2 solution, the blackened is calomel, and the no obvious change is silver chloride Hg2Cl2 + SNCL2 + 2 HCl = 2 Hg + H2SNCL6

3. Add water. The soluble is mercury HgcL2, the insoluble is calomel Hg2Cl24, adding excess ammonia, and then dissolving the zinc salt after producing a white precipitate, and the insoluble is the aluminum salt Zn2+ +4 NH3 = [Zn(NH3)4]2+

Choose. DA is not feasible because.

Phenolphthalein. In neutral environments, the ridges are colorless in both neutral and acidic environments.

b is not feasible and neither CO2 nor N2 is supported.

Wooden strips. of combustion.

c No, the state is feasible, all are strong acids, and they all turn red.

d feasible, sodium hydroxide.

Soluble in water, whereas calcium carbonate is insoluble in water and hence can be distinguished.

d(a No, phenolphthalein is colorless in neutral acidity; b No, both CO2 and N2 are inert hand sensitivity; c

No, all the potatoes will turn red if they are sour; Shake d

Yes, sodium hydroxide is soluble in water, while calcium carbonate is insoluble and can be distinguished).

Answer] D Answer Analysis] Test Question Analysis: A. Starch solution belongs to colloids, sucrose soluble jujube refers to solutions that belong to solutions, colloids can produce Tyndall phenomenon, solutions cannot, can be identified, correct; b. Oxygen supports combustion, carbon dioxide does not support combustion, so use the burning wood to identify oxygen and carbon dioxide, so that the carbon dioxide extinguished by the wood strips, the combustion is more vigorous is oxygen, correct; c. Dilute sulfuric acid rain zinc reacts to produce fiber and eliminate gas, which does not react with copper, which can be identified and correct; d. Sucrose and salt dissolved in water are colorless solutions, and water cannot be added to identify.

Test center: Examine the judgment of the identification method of the material that destroys the rock.

[Answer] a [answer analysis] test analysis: to identify substances should grasp the difference in the properties of the substance, through physical or chemical methods to distinguish, a, pure water and mineral water are colorless and clear liquid, so the identification of pure water and mineral water, by observing whether it is clear can not be identified, wrong, b, identify hard water and soft water, with soapy water, there is scum or less foam is hard water, more foam is soft water, correct, c, identify water and hydrogen peroxide solution, add manganese dioxide, observe whether there are bubbles, there are bubbles, for hydrogen peroxide solution, no phenomenon for water, correct, d, identify carbon dioxide and nitrogen, add clarified lime water, shake, observe whether it becomes turbid, become turbid for carbon dioxide, no phenomenon for nitrogen, correct, so choose a

Test Place: Chemical properties of common substances.

The first group, benzene, propyne, and a cycloene, using agno3, can get a white precipitate of propylene, the remaining two add acidic potassium permanganate, the faded one is a cyclone, the rest is benzene, benzene, the solution will be stratified.

Using newly produced copper hydroxide, heating, the brick-red precipitate is propionaldehyde, the acid potassium permanganate is used, the faded one is alcohol, and the remaining one is acetone.

The first is oxalic acid, which can be used with acidic potassium permanganate, the faded is oxalic acid, and the remaining one is adipic acid.

Using ferric chloride, the one that turns purple is salicylic acid, the remaining two use sodium bicarbonate, and the one with gas is the acid.