"Amount and Concentration of Substances" Amount of Substances PPT

Description

"Amount and Concentration of Substances" Amount of Substances PPT

Part One: Goals and Competencies:

1. Preliminarily learn how to prepare a solution with a certain amount and concentration of a certain substance, and possess basic knowledge and skills in chemical experiments. (Scientific inquiry and innovation consciousness)

2. Know the meaning of the amount and concentration of a substance, and use the relationship between the amount of a substance, its molar mass, the molar volume of a gas, and the amount and concentration of a substance to make simple calculations. (Macroscopic identification and microscopic analysis)

3. Understand the application of the quantity and concentration of substances in production and life. (Scientific attitude and social responsibility)

PPT on the amount and concentration of substances, part 2: independent preview to explore new knowledge

1. Amount concentration of substance and mass fraction of solute

1. mass fraction of solute

(1) Concept: The ratio of _____ mass to _____ mass in the solution.

(2) Expression: _____________=_______________.

2. The amount and concentration of a substance in a solution

(1) Concept: represents the _____ of solute B contained in the solution with unit _____.

(2) Symbol: _____, common unit: _____.

(3)Expression: ______.

In the expression of the concentration of a substance, V represents the volume of the solution. When performing simple calculations, it is necessary to distinguish whether the given volume is the volume of the solution. The volume of the solution is not equal to the volume of the solvent.

2. Preparation of solutions with a certain amount and concentration of a substance

1. Special instrument for preparing concentration solutions of a certain substance - volumetric flask

(1)Structure and specifications of volumetric flask

(2) Selection and use of volumetric flasks

① The volumetric flask is a special instrument for preparing quantitative and concentration solutions of substances. The selection of volumetric flasks should follow the principle of "large and close": the volume of the solution to be prepared is equal to or slightly smaller than the volume of the volumetric flask.

②Check whether the volumetric flask is leaking before use. Inspection procedure: add water → cork the bottle → stand upside down → check for leaks → stand upright, rotate the bottle stopper 180° → stand upside down → check for leaks.

③ Pay attention to the "five don'ts" when using a volumetric flask: it cannot dissolve solids; it cannot dilute concentrated solutions; it cannot be heated; it cannot be used as a reaction vessel; it cannot store solutions for a long time.

2. Prepare 100 mL of 1.00 mol·L-1 sodium chloride solution

(1) If 480 mL Na2CO3 solution is required for an experiment, what volumetric flask should be used?

[Tips]500 mL volumetric flask.

(2) What are the differences in the instruments required to prepare a solution of a certain substance concentration using concentrated sulfuric acid and solid NaOH?

[Tips] The difference between the two methods is the difference in weighing. One uses a graduated cylinder to measure the volume of the liquid, and the other uses a pallet balance to weigh the mass of the solid. When preparing concentrated solutions, tray balances and medicine spoons are not needed.

PPT on the amount and concentration of substances, the third part: core breakthroughs and difficult difficulties

Calculation of the amount and concentration of relevant substances

1. Calculation of the amount and concentration of relevant substances

(1) Basic formula for calculation: c=nV=mV·M.

(2)Basic types and methods of calculation:

①The mass of the solute is known

②The number of certain particles in the solution is known

③Calculation of the amount and concentration of gas solute substances under standard conditions

2. Conversion of substance concentration and solute mass fraction

(1) Conversion formula: cB=1 000ρwM mol·L-1.

M: molar mass of solute B ρ: solution density (g·mL-1).

(2) Derivation method

Assume the solution volume is 1 L,

Then cB＝nBV＝ρg·mL－1×1 000 mL×wMg·mol－11 L

=1 000ρwM mol·L-1.

3. Dilution and mixing of solutions

(1) Dilution rule

①Language description: Dilute a concentrated solution with water. The amount and quality of the solute remain unchanged before and after dilution.

②Formula: c(rich)·V(rich)=c(thin)·V(thin).

(2) Mixing rules

①Language description: Two solutions of the same solute with different concentrations are mixed. After mixing, the total amount (or total mass) of the solute is equal to the sum (or the sum of the masses) of the solute substances in the two solutions before mixing.

②Formula: c1•V1+c2•V2=c(mixed)•V(mixed).

PPT on the quantity and concentration of substances, the fourth part: meeting standards in class and improving quality

1. Take 100 mL from 1 L 1 mol·L-1 KOH solution. The following statement about this 100 mL solution is incorrect ()

A. The amount concentration of the substance is 0.1 mol·L-1

B． The density is the same as the original solution

C． The amount of substance containing KOH is 0.1 mol

D． The mass fraction of the solute is the same as the original solution

A　The solution is homogeneous. Take 100 mL from 1 L 1 mol·L-1 KOH solution. The substance concentration, solute mass fraction and density remain unchanged. The amount of KOH-containing substances in the 100 mL solution taken out is 1 mol·L-1×0.1 L=0.1 mol. ]

2. There is a bottle of solution in the laboratory, and the label is marked "BaCl2 0.2 mol·L-1". The following is a student's description of the solution. The correct one is ()

A. To prepare 500 mL of this solution, dissolve 0.1 mol BaCl2 in 500 mL of water

B． The substance concentrations of Ba2+ and Cl- are both 0.1 mol·L-1

C． Dilute the solution in the bottle twice, then the c(Cl-) of the solution obtained is 0.2 mol·L-1

D． Take half of the solution from the reagent bottle, then the substance concentration of the solution taken is 0.1 mol·L-1

C: Error A, 500 mL is the volume of solvent water, not the volume of the solution. It should be 0.1 mol BaCl2 dissolved in water to prepare a 500 mL solution, and its concentration is 0.2 mol·L-1; Error B, from " BaCl2 0.2 mol·L-1" and the material composition can be seen that the substance concentrations of Ba2+ and Cl- are 0.2 mol·L-1 and 0.4 mol·L-1 respectively; for C, c(Cl-)=0.4 mol· L-1, the amount of ionic substances remains unchanged before and after dilution, then the bottle solution is diluted twice, then c(Cl-)=V×0.4 mol·L-12V=0.2 mol·L-1 of the obtained solution. ]

3. The picture shows part of the content on the label of the sulfuric acid reagent in a school chemistry laboratory. According to this, the following statement is wrong ()

A. The concentration of the sulfuric acid is 9.2 mol·L-1

B． The mass of 100 mL of sulfuric acid is 184 g

C． The molar mass of sulfuric acid is the same as the molar mass of phosphoric acid (H3PO4)

D． Take 62.5 mL of this sulfuric acid and dilute it to 250 mL to obtain a concentration of dilute sulfuric acid of 4.6 mol·L-1

Keywords: Free download of the PPT courseware for high school chemistry compulsory course 1 of the People's Education Press, PPT download of the amount and concentration of substances, PPT download of the amount of substances, .PPT format;

For more information about the PPT courseware "Amount Concentration of Substances Amount of Substances", please click the Amount Concentration of Substances ppt Amount of Substances ppt tab.

"Physical Quantities Commonly Used in Chemistry - Quantity of Substances" Understanding Chemical Science PPT Courseware (Lesson 3: Amount and Concentration of Substances):

"Amount of Physical Quantities Commonly Used in Chemistry" Understanding Chemical Science PPT Courseware (Lesson 3: Amount and Concentration of Substances) Part One Content: Learning Objectives Course Standards 1. Use the amount of substances, molar mass, molar volume of gases, and the amount and concentration of substances The interrelationship between...

"Commonly used physical quantities in chemistry - the amount of matter" PPT courseware for understanding chemical science (lesson 2: molar volume of gases):

"Amount of Physical Quantities Commonly Used in Chemistry" Understanding Chemical Science PPT Courseware (Lesson 2: Gas Molar Volume) Part One Content: Learning Objectives Course Standards Use the relationship between the amount of matter, molar mass, and gas molar volume to perform simple calculations . nuclear..

"Commonly used physical quantities in chemistry - the amount of matter" PPT courseware for understanding chemical science (lesson 1, the amount of matter and its unit molar mass):

"Amount of Physical Quantities Commonly Used in Chemistry" Understanding Chemical Science PPT Courseware (Lesson 1 Amount of Substance and Its Unit Molar Mass) Part One Content: Learning Objectives Course Standards Can understand the composition of matter and its chemical changes based on the amount of matter, and use The amount of matter,...

File Info

Update Time: 2024-10-03

This template belongs to Chemistry courseware People's Education Press High School Chemistry Compulsory Course I industry PPT template

Preview