What are the required knowledge points of the chemistry academic proficiency test?

The required knowledge points of the chemistry academic proficiency test are as follows:1. Sprinkle concentrated alkali on the test bench, neutralize it with dilute acetic acid first, and then wash it with water to clean the draft height. If the concentrated alkali is stained on the **, it is advisable to rinse it with a large amount of water first, and then apply the boric acid solution.

The concentrated alkali is splashed in the eyes, washed with water and then rinsed with a boric acid solution.

2. If there is a fire in a small area of alcohol and other flammable organic matter, it should be quickly covered with a wet rag.

3. Evaporation: Transfer the filtered clear solution to the evaporation dish, heat, and stir with a glass rod to prevent droplets from splashing. When there is a large amount of solids, the heating is stopped, and the waste heat is evaporated. A white solid is produced in the evaporation dish.

4. In order to remove the impurities, the reagent added by Qingyuan should not be "appropriate", but "excessive"; However, excess reagents must be easily removed during subsequent operations.

5. The mass possessed by a substance per unit of substance is called molar mass.

The required knowledge points of the chemistry academic proficiency test are:

1. Atomic radius.

1) With the exception of the first period, the atomic radius of the periodic elements (except the noble gas elements) decreases with the increasing atomic number.

2) The atomic radius of elements of the same group increases from top to bottom as the number of electron layers increases.

2. Elemental valence.

1) Except for the first period, from left to right in the same period, the positive valence of elements increases from alkali metal +1 to +7, and the negative valence of non-metallic elements increases from carbon group -4 to -1 (except for fluorine without positive valence and +6 valence for oxygen in the same period).

2) The positive and negative valences of elements in the same main family are the same.

3) The bridge has a single quality and shows zero price.

3. The melting point of the element.

With the increase of atomic number, the melting point of the elemental element increases and decreases with the increase of the atomic number. From top to bottom, the melting point of the elemental element decreases, and the melting point of the non-metallic element increases.

4. The metallicity and non-metallic properties of elements (and their judgments).

1) The number of electron layers of an element in the same period is the same. Therefore, as the number of nuclear charges increases, the easier it is for atoms to gain electrons, decreasing metallicity from left to right, and increasing non-metallic properties.

2) The number of electrons in the outermost shell of the same main group element is the same, so with the increase of the number of electron layers, the Xiaoqing atom is more likely to lose electrons, increasing the metallicity from top to bottom, and decreasing the non-metallic property.

a.Raise the temperature faster.

b.Add the right amount of water and acid to dilute it slowly.

c.Add a small amount of CuSO4 to form a galvanic cell of the acceleration.

d.The amount of hydrochloric acid added in a larger concentration becomes more.

OH- has the number of buried potatoes and the same number of electrons as 9 and 1010

9 10 (right).

Selecting a concentrated bend H2SO4 will passivate the iron or aluminum can, forming an oxide film on the surface, thereby blocking the reaction.

The meaning of the question is: there is no hydroxyl group in the original organic matter, and through which of the following reactions can the hydroxyl group be present in the product?

Esterification: acid dehydroxyl alcohol dehydrogenation.

Substitution: Halogenated hydrocarbons react with an aqueous solution of sodium hydroxide to produce alcohols and salts that react to the chlor.

Elimination: Under the condition of heating concentrated sulfuric acid, this alcohol is either dehydrated by single molecule to form olefins, or dehydrated by intermolecular dehydration to form ethers.

Addition: The olefin undergoes an addition reaction with water to produce the corresponding alcohol.

Hydrolysis: The hydrolysis of halogenated hydrocarbons is the same as the elimination of alcohols, which are the reaction of halogenated hydrocarbons with the aqueous solution of sodium hydroxide to form alcohols and corresponding salts.

Oxidation: Olefins are not completely oxidized to generate alcohol (high schools do not require olefins to be oxidized into alcohol).

4.Bonus 5Hydrolysis can lead to the introduction of hydroxyl groups.

1. Esterification reaction, only the hydroxyl group will be removed.

2. Substitution reaction: Generally, the hydrogen on the organic matter replaced by halogen cannot introduce the hydroxyl group.

3. The elimination of the Liqing reaction is to eliminate the pre-repentant molecule of the limb, and usually the hydroxyl group is eliminated.

4. The addition of olefins and water can introduce hydroxyl groups.

5. Hydroxyl groups can be introduced into the hydrolysis of halogenated hydrocarbons.

6. Oxidation will only get farther and farther away from the hydroxyl group.

Alcohol can be obtained by hydrolysis of esters. Hydrolysis is a special substitution. Ethanol can be obtained by addition of ethylene to water.

A n2 molar mass 28 The first amount of the substance is 56 28 = 2molb The water under the standard condition is liquid, and the density is calculated according to the number l of 1000g The total amount of the pure molar mass of the substance is 18g 22400 18 = 1244mol

cd: What constant is that, so here's B

I have done this question, the condition is wrong, it should be: "100ml of 1mol·L-1 hydrochloric acid" added to the KSCN solution of ulfeng jujube KSCN solution does not appear blood red, indicating that there are no ferric ions in the solution, so it means that Fe + 2 FeCl3 = 3FeCl2

Again: Fe2O3 + 6HCl = 2FeCl3 + 3H2OFEO reacts with hydrochloric acid to form 2-valent iron ions, and Fe2O3 reacts with hydrochloric acid to form 3-valent iron ions. Fe reduces 3-valent iron ions to 2-valent iron ions, and the remaining Fe reacts with hydrochloric acid to form gas (hydrogen).

Since the mixture is completely dissolved, all the Cl ions in the hydrochloric acid form FeCl2, and the amount of Fe element can be obtained.

Therefore, the amount of Fe substance obtained by the final reduction of the base is .

The mass is grams.

It's simple. All hydrogen is made of elemental iron, so the amount of iron can be calculated.

Since there are no trivalent iron ions, all of them are ferrous chloride, and the total amount of iron can be calculated according to the amount of chlorine separated from the code, and then the quality of iron can be obtained.

If the information is incomplete, there is no way to calculate.

What is the concentration of hydrochloric acid?

A No, the bleaching principle of sulfur dioxide is to generate other unstable compounds, so that the color changes, when the outside temperature changes, the compounds decompose and lose bleaching.

The bleaching principle of hypochlorous acid is that it is oxidizing, oxidizing substances, and there is no change in heating.

b produces a large amount of SO2

c. Concentrated sulfuric acid cannot dry the alkaline gas NH3

d is the correct solution.

The bleaching principle of hypochlorous acid is to use its oxidizing properties, and the bleaching properties of sulfur dioxide are based on the principle of combining with substances to form colorless substances.

bSulfur dioxide is formed by combustion in air.

c. Ammonia is an alkaline gas, and concentrated sulfuric acid is an acidic desiccant, so concentrated sulfuric acid cannot dry ammonia.

A is different Sulfur dioxide is a reaction with water to colored substances, and hypochlorous acid is strongly oxidizing.

b Sulphur dioxide is not much to say.

c Ammonium sulfate is generated, and ammonia cannot be dried.

D right.