Organization: Check attendance, divide into groups, distribute worksheets.

STUDY SHEET NO. 2

II. Chemical properties

- From the electron configuration of the S atom, comment on the number of outermost electron shells and the number of single electrons in the ground state and excited state.

- Deduce the possible oxidation numbers of S in the compounds. In which compounds does S have an oxidation number of - (negative) and in which compounds does S have an oxidation number of + (positive)?

- From the oxidation numbers of S, predict the chemical properties of the element S. Compare with the element O2 . State the chemical reactions that demonstrate the properties of S.

Experiments demonstrating the chemical properties of sulfur.

Experiment 1: H2 gas reacts with S

Experiment 2: O2 gas reacts with S

Observe the experiment, comment on the phenomenon (if there is an experiment) and write the reaction equation, determine the role of S and the change in oxidation number of S in these reactions, read the names of the products formed.

STUDY SHEET NO. 3

III. Application

Observe the images in the E-book and through practice, list some applications of sulfur in life and industry that you know.

Do you know what vulcanized rubber is? Why do people vulcanize rubber?

STUDY SHEET NO. 4

IV. Sulfur production

1. From what raw materials can sulfur be extracted?

2. How do people exploit free sulfur?

3. State the principle and write the chemical reaction used to prepare sulfur from compounds. In addition to the effect of producing S, what significance does the method of producing S from compounds have in protecting our living environment?

2. Check old lesson: No check

3. Create a problem situation

What are the allotropic forms of sulfur? How are these allotropic forms similar and different in terms of physical and chemical properties?

B. TEACHING ACTIVITIES

Activity 1 : Study the physical properties of S.

Teacher's activities

Student activities		Knowledge content
- Ask students to discuss and present the issues in worksheet number 1. - Let students see the E-book during the discussion. - Summarize the ideas for students.			Conduct a discussion and take notes. - 1 group presents to the class. - Other groups give comments. - Summarize and take notes in your notebook.		I. Physical properties of S 1. Two allotropic forms of S - Is a yellow, brittle solid. - Insoluble in water but soluble in organic solvents (alcohol, benzene, ...). - Sulfur has two allotropic forms: triclinic sulfur (S α ) and monoclinic sulfur (S β ). Density: S > S Durability: S < S  t 0 nc : S < S 
2. The effect of temperature on molecular structure and physical properties ofsulfur
	Temperature	Status	Color	Molecular structure
	< 113 o C	snake	Yellow	S 8 , S α or S β crystal ring
	119 o C	liquid	Yellow	S 8 loop, flexible
	187 o C	viscous	reddish brown

Maybe you are interested!

445 o C	steam	orange	S 6 ; S 4
1400 o C			S 2
1700 o C			S
For simplicity, people denote it as S without using the molecular formula S8 in chemical reactions.

Activity 2: Learn about the chemical properties of S

Teacher's activities

Student activities

Knowledge content

- Ask students to discuss and present the issues in worksheet number 2.

- Let students see the E-book during the discussion.

- Summarize the ideas and let students copy the work.

Conduct a discussion and take notes.

- 1 group presents to the class.

- Other groups give comments.

- Summarize and take notes in your notebook.

II. Chemical properties

1. Oxidizing properties

a. Reaction with metals → sulfide salt

Al + S  t Al2S3(Aluminum

sulfide)

Fe + S  t FeS (Iron (II)

sulfide)

Hg + S HgS (Mercury)

(II) sulfide)

b. Reaction with H2 → Hydrogen sulfide gas

H 2+ S  t H2S

 Oxidation number of S: 0 → -2.

2. Reducing properties: Reacts with PK

S + O 2 → SO 2 S + 3F 2 → SF 6

 Oxidation number of S: 0 → +4, +6.

Activity 3: Learn about the applications of S

Teacher's activities

Student activities

Knowledge content

- Ask students to discuss and present the issues in worksheet number 3.

- Let students see the E-book during the discussion.

- Summarize the ideas and let students copy the work.

Conduct a discussion and take notes.

- 1 group presents to the class.

- Other groups give comments.

- Summarize and take notes in your notebook.

III. Application

- 90% of the sulfur mined is used to produce H 2 SO 4 .

- 10% remaining sulfur

It is also used to vulcanize rubber, produce pulp bleach, matches, ebonic plastics, pharmaceuticals, dyes, pesticides, and fungicides.

in agriculture...

Activity 4: Learn about sulfur mining methods

Teacher's activities

Student activities

Knowledge content

- Ask students to discuss and present the issues in worksheet number 4.

- Let students see the E-book during the discussion.

- Summarize the ideas and let students copy the work.

Conduct a discussion and take notes.

- 1 group presents to the class.

- Other groups give comments.

- Summarize and take notes in your notebook.

IV. Sulfur production

1. Sulfur mining : used to exploit sulfur from underground (Frasch method).

Super hot water compression (170 0 C)

into underground S mine to pump underground S up.

2. Chemical method

a) Burning H2S in the absence of air

2H 2 S + O 2 → 2S + 2H 2 O

b) Use H 2 S to reduce SO 2

2H 2 S + SO 2 → 3S + 2H 2 O

C. END OF LESSON ACTIVITIES

1. Consolidate knowledge

- Let students summarize the basic knowledge learned in the lesson.

2. Homework – Research

- Ask students to do the exercises in the E-book at home.

IV. TEACHING EXPERIENCES

................................................................ ................................................................ ..................

2.6.3. Lesson plan for the lesson "Hydrogen sulfide"

Lesson 44: HYDROSULFUDE

I. OBJECTIVES

1. Knowledge

Students know:

- Physical properties, natural state and preparation of hydrogen sulfide.

- Weak acidity of hydrosulfuric acid.

- Properties of sulfide salts.

Students understand:

- Molecular structure, strong reducing properties of H 2 S.

2. Skills

- Predict, test, and conclude about the chemical properties of H 2 S.

- Write a chemical equation to illustrate the properties of H 2 S.

- Distinguish H2S from other known gases such as oxygen, hydrogen, chlorine...

- Solve exercises: calculate the volume or mass percentage of H2S gas in the reaction mixture or product; synthesize exercises with related content.

3. Attitude

Training for students:

- Careful, precise, passionate about science.

- Awareness of environmental protection, knowing how to use chemicals to benefit humans and not harm the environment.

4. Focus: Weak acidity and strong reducing properties of H 2 S.

II. PREPARATION

1. Teacher

- Give E-book to students and instruct on how to use it.

2. Students

- Read the E-book and learn the lesson content in advance.

III. ORGANIZING TEACHING ACTIVITIES

A. INITIAL ACTIVITIES

1. Organization: Check attendance, divide into groups, distribute study sheets.

STUDY SHEET NO. 1

I. Molecular structure

Based on the molecular formula of H2S , the outer electron configuration and electronegativity of S, let's:

- Write the structural formula of H 2 S. Explain the chemical bonds in the H 2 S molecule.

- Determine the oxidation number of S in H 2 S.

STUDY SHEET NO. 2

II. Physical properties

- Using your practical knowledge, please tell me the physical properties of hydrogen sulfide. (State, color, taste, solubility in water, heavier or lighter than air).

- Read the following information and tell whether hydrogen sulfide is toxic?

In November 1950, in Mexico, a cooling plant in Pozarica released a quantity of hydrogen sulfide gas, a compound of sulfur and hydrogen. Within 30 minutes, the gas, along with the city's white smog, killed 22 people and poisoned 320.

STUDY SHEET NO. 3

III. Chemical properties

Experiment 1: Test the properties of H2S gas using moist blue litmus

When dissolved in water, what solution does H2S gas form ? How strong is this acid? Compare it with carbonic acid.

Consider the reaction between H2S and NaOH, when does an acidic salt form and when does a neutral salt form?

Experiment 2: H2S gas reacts with oxygen. Comment on the phenomenon in 2 cases:

+ Block the glass across the flame (lack of oxygen).

+ No glass (excess oxygen).

From there, comment on the properties of H 2 S in this experiment. Why does H 2 S have those properties? Write an illustrative equation, paying attention to the reaction conditions.

STUDY SHEET NO. 4

IV. Natural state – Preparation

1. Observe the pictures in the E-book and tell us the natural state of hydrogen sulfide.

2. H2S gas is a toxic chemical to humans, so people do not prepare it industrially but only prepare a small amount in the laboratory to study its physical and chemical properties.

Please present the chemical method for preparing H2S in the laboratory.

STUDY SHEET NO. 5

IV. Properties of sulfide salts

- Observe the solubility table of salts, comment on the solubility of sulfide salts: which salts are easily soluble, which salts are insoluble, what color?

- Draw out the way to identify sulfide radicals.

2. Review old lesson

State the basic chemical properties of sulfur and illustrate them with equations?

3. Create a problem situation

Why do sewers, or public waste places,... often have a foul smell? What gas is the main cause of that smell? Is it toxic? So today we will consider what kind of gas it is?