Question related to solution concentration, what is the concentration of solution?

Concentration Concentration refers to the share of a species in the total population.

Commonly used concentration expressions are:

1.Weight percentage: Generally used most commonly.

2.Volume Percentage: Commonly used for wine representation.

3.Volumetric molar concentration: commonly used in chemistry.

4.Gravimetric molar concentration.

Molar fraction The broad concept of concentration refers to the amount of solute in a certain solution or solvent; This general notion of concentration, like the notion of "quantity", has no clear meaning; Traditionally, the amount of the solution involved in the concentration is taken as the volume, the amount of the solution is often taken as the mass, and the amount of solute is taken as the quantity, mass, and volume of the substance.

It has been specified that the concentration in the narrow sense is the abbreviation of the quantity concentration of the substance, and was previously called the volume molar concentration (molarity), which refers to the amount of solute B in each liter of solution, with the symbol C, and the unit is mol l or mol dm3, that is:

cb≡nb/v

In view of the fact that the volume of the solution changes with temperature, resulting in the quantity concentration of the substance also changing with temperature, in strict thermodynamic calculations, in order to avoid the influence of temperature on the data, the mass molality concentration is often used instead of the quantity concentration of the substance, which is defined as the amount of solute species per 1kg of solvent, the symbol is m, and the unit is mol kg, i.e.:

mb≡nb/wa=nb/（na ma）

where B is the solute and A is the solvent. For example, m(NaCl)=, which means that there is NaCl per 1kg of solvent.

In addition to the mass molar concentration, the concentration notation that does not change with temperature also has the mass fraction, formerly known as the mass percentage concentration, which is the ratio of the mass of the solute to the mass of the solution.

Finally, it should be mentioned that the concentration of the solution is independent of the amount of the solution, and if you take a drop from a bottle of NaCl solution, the concentration of that drop is still there. This may seem like nonsense, but it's not. Because there are two types of physical quantities, the first type of physical quantities have additiveness, such as mass, quantity of matter, volume, length, ......, this kind of physical quantity is called a broad measure; The other type of physical quantity is not additive, and this kind of physical quantity is called the intensity quantity.

Concentration is the amount of intensity. In addition, pressure (pressure), temperature, density, etc. are also strength measures.

The solution concentration % is the percentage of solute in the total solution mass.

But the molar concentration is the percentage of solute in the total volume of the solution.

What you are talking about should be the mass fraction of the solution.

Solution concentration refers to the percentage concentration of the solution. Percentage concentration of solution (concentration can be calculated as the number of grams, gram molecules, or gram equivalent of solutes in a given solution.) ) is the percentage of the weight of the solute contained in a solution (generally a unit solution).

When a soluble substance is dissolved in a solvent, the density of distribution in that solvent is expressed as a percentage, called the percentage concentration of the solution (mass fraction of the solution), which is often expressed as a c% (which can also be expressed as w).

Formula

The formula for calculating the percentage concentration of the solution is:

Mass percentage concentration of the solution Soluble mass The mass of the solution is 100%.

Where, solute mass solvent mass and solution mass.

The above content refers to: Encyclopedia - Percentage Concentration of Solution.

1.Knowing the mass m of the solute, and the volume v of the solution, assuming that the molar mass of the solute is m The molar concentration of the solute is c=m mv2The amount of the substance of the solute is known n, and the volume of the solution v, and the molar concentration of the solute is c=n v 3

The molar mass of the solute is known to be the early mass fraction w, and the density of the solution p, the molar mass of the solute is m The molar concentration of the solute is C = 1000 pw m 4The mass of the solution m is known, and the volume v of the solution, the density of the solution w and the molar concentration of the solute is c = 1000 mw mv

The basic relationship of the nucleus problem of thick shirt or digging: concentration = [solute mass solution mass * 100%] solution = [solute mass] + [solvent mass].

1 Pinyin 2 Annotations.

róng yè de nóng dù

The amount of solute contained in a certain amount of solution is called the concentration of the solution. The concentration of the solution is a quantitative marker that expresses the relative presence of solute and solvent in the solution. People stipulate different standards according to different needs and convenience of use, and there are different solution concentrations.

Therefore, the concentration of the same solution with different standards is expressed differently. There are various ways to express the concentration of a solution, which can be grouped into two broad categories. The first is mass concentration, which indicates the relative amount of solute and solvent in a solution of a certain mass, such as mass percentage concentration, mass molar concentration, ppm concentration, etc.

The other type is volume concentration, which indicates the amount of solute contained in a certain volume solution, such as the amount of concentration of the substance, the volume specific concentration, the gram concentration, etc. The value of the mass concentration does not change with the change of temperature, whereas the value of the volume concentration changes with the change of temperature. Some concentrations have been obsolete, such as the equivalent concentration that has been discarded, and the gram molecular concentration has been replaced by the amount concentration of the substance.

Other concentrations are being replaced by new legal units of measurement, such as mass percentage concentrations and ppm concentrations, which will be replaced by mass fractions.

In what case, concentration = solute solute + solution are all wrong! Please make sure the princess understands the following concepts thoroughly:

Solute --- this is a substance in solution that is dissolved by a solvent. For example, salt in the salt solution of Bisanchen.

Solvent --- This is a substance that can dissolve solvents. For example, water in a table salt solution.

Solution--- which is a mixture of solvents and solutes. For example, salt water (salt + water).

Percent concentration--- This is the mass fraction of the solvent in solution.

Solubility --- the mass (grams) in which 100 grams of solvent can dissolve the solute at a certain temperatureFor example, at a certain temperature, 100 grams of water can dissolve up to 36 grams of table salt, then we say that the solubility of table salt at this temperature is 36 grams.

If you grasp the above concepts, the problem of mass percentage concentration and solubility is clear. The following topic is used to calculate the concentration and solubility problems.

Examples. At a certain temperature, 50 grams of water can dissolve up to 18 grams of table salt, what is the mass fraction (percentage concentration) of table salt at this time? What is the solubility of table salt?

Percent concentration = 100% solute mass Solution mass = 100% 18 (50+18)=

Solubility = 100 18 50 = 36 grams.

The amount of the substance of the crystal is m b, and 1 a·h2o contains 1 a, so the amount of a·h2o is the amount of a substance, and the concentration of the substance is c=n v=(m b) (v 1000).

The mass of A in the Jingxiao Qiqi is M*(B-18) B, the mass of the mixed solution is Vd, and the mass of water is Vd-[M*(B-18) B], and then let the solubility of A in the liter of Li is S, according to the definition of solubility there are S 100=[M*(B-18) B] [VD-[M*(B-18) B], and S can be solved.

The mass of A in the crystal is m*(b-18) b, the mass of the mixed solution is VD, and the solute mass fraction is [m*(b-18) b] VD*100%.

4.greater than 10g, because A dissolves in water will absorb water to form A·H2O, resulting in a decrease in the quality of the solvent, and the mass of the precipitated crystals is greater than 10g.

The amount of the substance of hydrochloric acid is:

The amount of the substance of sodium hydroxide is.

The amount of substance remaining after the reaction is Leeson.

Note that this question asks you the concentration of the amount of the mixed solution substance, not the concentration after dilution, so which mu mu of the body is rollable after mixing.

So the concentration is: