The perception of the solution is correct, and the statement about the solution is correct

aOne or several substances are dispersed into another substance, forming a uniformity.

1. A stable mixture is called a solution.

That's right. The B solution is a colorless, transparent, homogeneous, and stable mixture. Copper sulphate solution blue.

c. Vegetable oil dissolves into gasoline, feasible and unstable emulsion.

Vegetable oil is dissolved in gasoline to form a solution.

After a cup of completely dissolved sugar water is left for a while, the upper part of the solution must be sweeter than the bottom half.

Wrong. The solution is homogeneous, and the properties of all parts are the same.

The mistake of choosing a b is that the solution is not all colorless.

c The mistake is that vegetable oil is organic matter, gasoline is organic matter, and organic matter is soluble in organic matter.

The upper half is as sweet as the lower half, because it is completely dissolved into a solution, stable and homogeneous.

Only a correct, standard solution definition.

B: The solution is not necessarily colorless, and the copper sulfate solution is blue.

C: I haven't tried it, I think it should be miscible, but vegetable oil and gasoline are not solutions, they are mixtures, and the composition is quite complicated.

D: Sugar water is not a solution, it is a mixture, according to experience, it is obviously the bottom half of the sweet, hehe!

ab error because the solution can be colored. For example, alloys.

C false, because vegetable oil can be dissolved into gasoline to form a solution Because gasoline and vegetable oil are both oil-soluble organic solvents, according to the principle of similar miscibility, they are miscible, so they are solutions.

D false. Sugar water is the solution. It is stable and homogeneous. So it won't be sweetened.

So choose A

a. Because there is an interval between molecules, the volume of the solution is not equal to the volume of the solute plus the volume of the solvent, so A is wrong;

B. Since the solution is composed of two parts, solute and solvent, the mass of the solution = the quality of the solute + the quality of the solvent, so B is correct;

c. Because the characteristics of the solution are uniform.

1. Stable and uniform means that all parts of the solution have the same properties, so C is wrong;

d. Because oil is insoluble in water and cannot form a solution, there is no such thing as solute and solvent, so D is wrong. Therefore, choose B

Test Points: This question examines the concept, composition and characteristics of solutions.

Comments: It is important to know that the addition of the volume of solute and solvent is not equal to the volume of the solution, but the mass can be added; Only solutes and solvents are present in the solution, and there are no solutes and solvents at all for suspensions and emulsions.

Answer C analysis: A solution is a mixture of solutes and solvents, and solutes can be solids, liquids or gases; According to the properties of the solution and the saturated solution and other related knowledge points, the solution is analyzed and judged

Answer: a. The solution is a mixture with uniformity and stability, but it is not necessarily colorless, for example, the copper sulfate solution is blue, so a is wrong;

b. The solute can be a gas, a solid or a liquid, such as the solute in the alcohol solution The alcohol is the liquid, and the solute sulfuric acid in the dilute sulfuric acid is the liquid, so B is wrong;

c. If the temperature of the solution is limited, the solubility of the solid substance in the same solvent is also limited, when the solution changes from unsaturated to saturated solution, the mass fraction of the solute must increase, but for the gas, the factors affecting its solubility are in addition to temperature and pressure, under the condition of keeping the temperature unchanged, reduce the pressure, and the solution can also be changed from an unsaturated solution to a saturated solution, so the mass fraction of the solute remains unchanged when it is just saturated, so c is correct;

d. For different solutes, or the same solute at different temperatures, there is no necessary connection between saturated solution and unsaturated solution, and the concentration and dilution of the solution are only a relative statement, and there is no relationship with whether the solution is saturated, but for the same solute, the concentration of saturated solution at the same temperature must be larger than that of unsaturated solution, so D is wrong

Therefore, choose C Comments: Know that there is no inevitable connection between concentrated solution and dilute solution and concentrated solution and dilute solution, and be proficient in the solubility factors that affect solid and gaseous substances

A false, such as iodine is ethanol as a solvent.

B false, pure water is also a colorless, transparent liquid, a pure substance, not a solution.

C pair, adding NaOH to the brine can also form a solution.

d false, a certain amount of solvent, the more solvent added, the smaller the mass of the solution.

c There is something that does not dissolve in water, awrong.

Colored ones can also make a mistake in solutions such as CuSO4 (blue).

All solutes have a certain solubility d'errone.

Answer A Analysis: Depending on the solution is in a certain temperature and solvent, the solute is dissolved in the solvent to form evenly.

1. Stable mixture, when the external conditions are changed, the amount of solute in the solution may change, and then combined with the relationship between temperature and solubility to solve

Solution: a. Because the solubility of different substances is affected by temperature differently, such as the saturated solution of calcium hydroxide, the solubility becomes smaller when the temperature increases, and there is solid precipitation, and the solution is still a saturated solution, so the statement A is incorrect;

b. Due to the different temperatures, the dissolved mass of the substance is different, that is, the solubility of the substance is related to the temperature, so the statement b is correct;

c. In general, the solubility of the substance is determined by the nature of the substance itself, and for the substance that is easily soluble in water, the difference in the concentrated and dilute solution is only the amount of solute, so the C statement is correct;

d. From the concept of solution, it can be seen that one or several substances are dissolved in another substance to form even.

1. Stable mixture, the solute in the solution can be one or more, so the D statement is correct;

Therefore, choose a Comment: This question tests the understanding of solution, students should be familiar with the concept of solution and the relationship between solubility and temperature, and be familiar with the solubility of common substances affected by temperature to answer.

a. The solute in the solution can be one or more failed bond species, so a is correct;

b. The solution has uniformity.

1. Stable mixture, even.

1. The liquid that is determined by the stable ant is not necessarily a mixture, so B is wrong;

c. The saturated solution is not necessarily a concentrated solution, and the unsaturated solution is not necessarily a dilute solution, so C is wrong;

D. The solution has uniformity, and the density of each part is the same, so D is wrong to choose: A

a. After adding solute to water, the boiling point of the solution increases and the freezing point decreases, so A is wrong;

b. The characteristics of the solution: uniformity, stability, belonging to the mixture Colorless clear liquid is not necessarily a mixture such as water, so B is wrong;

c. The solute can be solid, liquid, or gas, so C is wrong;

d. The characteristics of the solution: uniformity, stability, and a mixture, so the properties of all parts of the solution are the same, so D is correct

Therefore, choose D

Answer: d. Before and after the solution is diluted with water, the quality of the solute must remain unchanged.

d. Before and after the solution is diluted with water, the mass of the solute must remain unchanged is the correct answer aThe solution must be a colorless, transparent mixture, or it can be colored, such as potassium permanganate solution, which is purplish-red.

b. When the amount of solvent remains the same, the more solute is added, the greater the mass of the solution must be, and the solute dissolution will not increase when it reaches saturation.

c. When the substance is dissolved in water to form a solution, the temperature of the solution must remain unchanged The temperature of sodium hydroxide solid dissolved in water increases.

Remember and the first price, it is not easy to answer the question, I hope our labor can be recognized, which is also the motivation for us to continue to move forward!