Tiểu luận hóa học: Dạy học bài axit nitric bằng tiếng anh

LESSON: NITRIC ACID A. OBJECTIVES Outline molecular structure, physical properties (state, color, density, solubility), application of HNO3 HNO3 is one of the strongest acids. HNO3 is a very strong oxidizer: oxidizes most metals, some nonmetals, many inorganic and organic compounds. Predict chemical properties, test predictions by experiment and draw conclusions. Observing experiments, photos ..., drawing comments on the properties of HNO3. Writing chemical equations of reduced molecular and ionic formations illustrating the chemical properties of concentrated and dilute HNO3. B. VOCABULARY

LESSON: NITRIC ACID

A OBJECTIVES

- Outline molecular structure, physical properties (state, color, density, solubility), application of HNO 3

- HNO 3 is one of the strongest acids.

- HNO 3 is a very strong oxidizer: oxidizes most metals, some non-metals, many inorganic and organic compounds.

- Predict chemical properties, test predictions by experiment and draw conclusions.

- Observing experiments, photos , drawing comments on the properties of HNO 3

- Writing chemical equations of reduced molecular and ionic formations illustrating the chemical properties of concentrated and dilute HNO 3

B VOCABULARY

nitric acid axit nitric physical properties tính chất vật lí

Modulation

method Phương pháp điềuchế solubility độ tan

laboratory

phòng thí nghiệm boiling point điểm sôi

in industry trong công nghiệp very soluble tan tốt

Teacher activities Hoạt động của giáo

viên

the light

ánh sáng

Student activities Hoạt động của học

sinh

protect

bảo quản

molecular formula công thức phân tử liquid chất lỏng

structural formula công thức cấu tạo Observingphenomenon the quan sát hiệntượng

cause gây ra browning in the air hóa nâu trong

không khí

Oxidation phản ứng oxi hóa highestchemotherapy hóa trị cao nhất

oxidation number số oxihóa Aqua regia Nước cường

thủy

Chemical

properties tính chất hóa học transport vận chuyển

reaction equation phương trình phản

ứng

protective oxide film lớp màng oxitbảo vệ prove chứng minh white precipitate kết tủa trắng

observe

unstable không bền nitrogen fertilizer phân đạm

C EXPRESSIONS

to be soluble/insoluble in tan/không tan trong

at standard temperature and pressure (s.t.p.) ở điều kiện tiêu chuẩn

to be produced = to be formed được tạo ra

to be broken down to bị phân hủy thành

to be kept tightly corked được nút chặt

to be (left) exposed to air được để ra ngoài không khí

D PLAN OF TEACHING

Activity 1: Molecular structure

Capacity development: The ability to

use chemical language and

problem-solving ability through the subject

- Teacher: Ask hs to give CTPT and

write CTCT of HNO3 molecule

- Hs: Answer

A NITRIC ACID:

I Molecular structure:

- CTPT: HNO3

- CTCT:

Activity 2: Physical properties

Capacity development: The ability to

use chemical language

- Teacher: Ask Hs to observe and study

the lesson content in the textbook,

drawing out the physical properties of

HNO

Hs: Indicate the state, color, durability

of water solubility, concentration of

concentrated HNO3 solution and

II Physical properties: Textbooks

- Colorless liquid, fuming in moist air

- Easily prone to heat or light decay → yellow dd

- Soluble in water at any rate, D = 1,53g / cm3, ts = 860C

specific gravity.

- Teacher: Comments, additions and

conclusions

Activity 3: General comments on the

chemical properties of HNO 3

Capacity development: The ability to

use chemical language, the ability to

solve problems through subjects, the

ability to apply chemical knowledge to

life

- Teacher: Ask students to write the

electrolyte equation of HNO3 and

determine the oxidation number of N

in the HNO3 molecule → Predict

properties?

- Hs: Answer

III Chemical properties:

- HNO3 → H + NO3- => is a strong acid

→ The highest OXH number can only be reduced => oxidation

Activity 4: Acidity of HNO 3

Capacity development: The ability to

use chemical language, teamwork

capacity and ability to write chemical

equations

- Teacher: Ask students to discuss and

state the general chemistry of acid?

- Hs: Discuss and state the chemical

properties: Change the color of purple

anemone to red, works with basic

oxides, bases, salts of weaker acids,

with metals

- Teacher: Ask students to complete the

first 4 properties in notebooks

- Teacher: If students are properties of

metals will not produce H2, so they

will be explored in the next section

1 Acidity: HNO3 is a strong acid

- Kneeling purple, works with basic oxides, bases, salts of weak acids

A strong acid with all the properties of an acid:

HNO3 → H + NO3 -makes red kneel, works with weaker oxides, bases, salts of acid

Ví dụ:

2HNO3 + MgO → Mg(NO3)2 + H2O 2HNO3 +Ca(OH)2 →Ca(NO3)2 + H2O 2HNO3 +CaCO3 → Ca(NO3)2 +CO2 +

H2O

Hs: Listening to come home to

perfection

Activity 5: Strong oxidation

properties of HNO 3 - Works with

metals

Capacity development: The ability to

use chemical language, the ability to

solve problems through subjects, the

ability to apply chemical knowledge to

life and group activities

- Teacher: Stating the strong oxidation

capacity of HNO3

- Gv: Oxidation of most metals (except

Au, Pt)

- Teacher: Demonstration experiments

between Cu effect with thick and thin

HNO3 dd to prove Ask students to

observe, discuss, raise phenomena?

- Hs: observe, discuss and make

comments, write chemical equations

- Teacher information: Often HNO3

dilutes to form NO; Special HNO3

forms NO2

- Teacher: Passive test presentation of

Al, Fe, Cr with cold concentrated

HNO3 solution

- Hs: observe, comment phenomena

2 Oxidation properties:

- HNO3 with OXH +5 number may be reduced to:

o +1 + 2 + 4 -3

N2, N2O, NO, NO2, NH4NO3 depending

on the HNO3 concentration and reducing ability of participating substances

a Effect on metals:

- Oxidation of most metals (except Au, Pt)

0 +5 +2 2 3Cu + 8HNO3 (l) → 3Cu(NO3)2+ 2NO+ 4H2O

0 +5 +2 4 Cu+4HNO3 solid → Cu(NO3)2+ 2NO2+2H2O

- Passive Fe, Al, Cr with solid, cool HNO3

Activity 6: Strong oxidation

properties of HNO 3 - Works with

nonmetals and compounds.

Capacity development: The ability to

use chemical language, the ability to

solve problems through subjects, the

b Non-metallic effect:

- Concentrated HNO3, hot OXH obtained some non-metallic C, S, P, obtained

NO2 6HNO3 + S→ H2SO4+ 6NO2+2H2O

ability to apply chemical knowledge to

life

- Gv: When heated, concentrated

HNO3 can oxidize some non-metals to

the highest level of oxh

Screening of experimental video:

HNO3 condensed with S

Hs observed, commented, wrote

reaction equations

- Teacher: Ask students to read part C

- Hs: Read the text

- Teacher: Give reaction between FeO

HNO3

- Hs: Write PTHH

c Effects on compounds:

- HNO3 special oxidize many inorganic and organic compounds

FeO+ 4HNO3 → Fe(NO3)3+NO2+ 2H2O

- Cloth, paper, sawdust, pine oil are destroyed when exposed to solid HNO3

Activity 7: Application of HNO 3

Capacity development: The ability to

use chemical language, the ability to

apply chemical knowledge to life

Hs studied textbooks said the

application of HNO3

IV Application: SGK

Activity 8: Modulation of HNO 3

Capacity development: The ability to

use chemical language, the ability to

solve problems through subjects

- Teacher: Ask questions: How is

HNO3 prepared?

- Teacher: For students to read,

observe picture 2.7 sgk

→ Ask hs to know how to prepare

HNO3 in the laboratory Write

chemical equations

V Modulation

1 In the laboratory: NaNO 3 (or KNO 3 ) crystals act with concentrated H 2 SO 4 , heated

NaNO3+H2SO4(đ)→ HNO3+NaHSO4

Hs: Answer 2 In technology: HNO 3 is produced in

three stages:

Axit nitric loãng có thể cô đặc đến 68% axit với một hỗn hợp azeotropic với 32% nước Để thu được axit có nồng độ cao hơn, tiến hành chưng cất với axit sunfuric

H2SO4 H2SO4 đóng vai trò là chất khử sẽ hấp thụ lại nước

4NH3 + 5O2 → 4NO + 6H2O (Pt, 850oC) 2NO + O2 → NO2

4NO2 + O2 + 2H2O → 4HNO3 Dung dịch axit nitric công nghiệp thường

có nồng độ 52% và 68% Việc sản xuất axit nitric được thực hiện bằng công nghệ Ostwald do Wilhelm Ostwald phát minh

Activity 9:

- Teacher: For hgk sgk research,

indicate the solubility characteristics of

nitrate salts; Write the electrolyte

equation for some salts

Hs: Answer, write electrolysis

equations

B Nitrate salt: M(NO 3 ) x

I Properties of nitrate salts:

1 Physical properties:

- All nitrate salts are water soluble and are strong electrolytes

Ca(NO3)2 → Ca 2+ + 2NO3

-KNO3 → K+ + NO3

-Activity 10:

- Teacher: Let students read and collect

information from SGK

H Ask hs to discuss to draw

conclusions about the pyrolysis

reaction of nitrate salts

Hs: Discuss for 3 minutes, present

2 Chemical properties:

-The nitrate salts are unstable by heat, when heated nitrate salts have strong OXH properties

- Decomposition products depend on the nature of the metal cation:

- Teacher: Comments, conclusions

- Gv: Ask hs to write the pyrolysis

equation of some salts: Al (NO3)3;

NaNO3; Pb (NO3)2

* Kim loại đứng trước Mg

t

→

muối Nitrit + O2

2KNO3

o

t

→

2KNO2 + O2

* Từ Mg đến Cu

o

t

→

Oxit kim loại +

NO2 + O2

2Cu(NO3)2

o

t

→

2CuO + 4NO2 + O2

* Kim loại sau Cu

o

t

→

Kim loại + NO2 + O2

2AgNO3 → 2Ag + 2NO2 + O2

3 Identify nitrate ions

In neutral, ion, NO3- does not have the oxidation When the available H+ ion, ion, NO3- is oxidatively like HNO3 And

so to realize the ion NO3- people lightly heated solution containing NO3- with metal H2SO4 diluted:

3Cu + 8H++2NO3-→3Cu2++2NO+4H2O 2NO + O2 → 2NO2

Không màu màu nâu

Activity 11:

- Teacher Let students study sgk and

find out the fact that nitrate salts have

applications?

Hs: Nitrogenous fertilizer, black

II Nitrate salt application:

E WORKED EXAMPLES

1 KNOWLEDGE - qualitative questions

Question 1: Nitric acid has CTPT as:

A HNO2 B HNO3 C HNO5 D H3NO4

Question 2: The atom N in the molecule HNO3 has the oxidation number:

A 1 B 2 C 3 D 5

Question 3: In the laboratory, people often prepare HNO3 words

A NaNO2 and concentrated H2SO4 B NaNO3 and concentrated H2SO4

C NH3 and O2 D NaNO3 and concentrated HCl

2 LEVEL OF LEARNING - qualitative questions

Question 1: Which of the following substances is not produced when metal reacts

with HNO3 acid?

A NO2 B N2O C N2O5 D NH4NO3

Question 2: Which of the following chemicals is used to distinguish 3 cool-thick dd:

HCl, HNO3, H2SO4

A Al B CuO C Cu D Fe

Question 3: Use the following chemicals to distinguish 4 packets of flour:

Cu, CuO, Fe, Fe2O3

A H2O B NaCl C NaOH D HNO3

Question 4: Add aluminum powder to dd HNO3 dilute, residue obtained NO, N2O and dd A Add excess NaOH to dd A to get X Gas X is:

A N2 B H2 C NH3 D NO2

3 LOW LEVEL OF APPLICATION - quantitative and qualitative exercises

Question 1: Dilute HNO3 solution reacts with all of the following series of substances:

A.FeO, FeS, Fe2O3, BaSO4 B Fe(OH)2, Fe(OH)3, H2S, FeS

C FeCO3, NaNO3, CuS, Cu2S D Fe(OH)2, Fe, K2CO3, NaCl

Question 2: Giving 19.5 grams of n-valent M metal dissolved in HNO3 solution to obtain 4.48 liters of NO gas (the only reducing product of N 5 in standard conditions) M

is metal:

A Mg B Cu C Fe D Zn

Question 3: Make 1 gram of Fe dissolved in 250 ml of 2M HNO3 solution to obtain the only reductant, NO, to neutralize the excess acid, it is necessary to use 100 ml of 1M NaOH solution So m has the value of:

A 2.8 grams B 8.4 grams C 5.6 grams D 11.2 grams

Question 4: Give 11,2 grams of a metal Z dissolved in a sufficient amount of HNO3, after the reaction obtained dd A and 2.28 liters of NO gas (in the standard) is the only reducing product Concentration dd A dried anhydrous salt with mass equal to:

A 55.6 grams B 48.4 grams C 56.5 grams D 44.8 grams

Question 5: M mg Mg completely dissolved in HNO3 solution, the reaction releases

N2O gas (the only reducing product of N+5) and the solution after reaction increases 3.9 grams So m has the value of:

A 2.4 grams B 3.6 grams C 4.8 grams D.7.2 grams

4 HIGH PERFORMANCE

Question 1: For substances: Fe, FeS, Fe2O3, Fe3O4, Cu2O, Na2S, Fe (OH) 3 How

many of these substances work with dilute HNO3 dd of the redox reaction:

A.7 B.6 C.5 D.4

Question 2: Add 19,2g Cu to 500ml of 1M NaNO3 solution then add 500ml of 2M

HCl solution The final reaction yields a solution of X and V liters of NO gas (the only reducing product of N 5 in the test condition) The value of V is

A 3.36 liters B 4.48 liters C 2.24 liters D 4.48 liters

Question 3: Give 27 grams of Al completely dissolved in HNO3 solution, the reaction causes the release of V liter of N2O, NO with molar ratio of 1: 1 (dktc) after the reaction of 29.3 grams of salt So V has the value of:

A 4.48 liters B 3.36 liters C 10.08 liters D Other results

EXPERIMENTAL QUESTIONS

Question 1: Conducting 2 experiments:

TN 1: Put some Cu powder in dilute HNO3 solution

TN 2: Put a few sets of Cu in a thick, cool HNO3 solution

Observe experiments, raise and explain phenomena by chemical equations

Question 2: When doing experiments with HNO3 can generate many toxic gases Suggest a method to prevent those gases from being released into the air

PISA QUESTION Question 1: Explain the verse:

“Contemplative rice peeked out from the edge

When listening to the thunder flag waving up "

F HOMEWORK

Question 1: By chemical methods, please show how to identify the following containers

of liquid solution: HNO3, KNO3, dilute H2SO4, KCl Write chemical equations that happen if they exist

Tutorial:

+) Use BaCl2 solution

+) Use AgNO3 solutions

+) Use purple kneeling:

Question 2: Write an abbreviated molecular and ion equation

a) NaOH HNO3 →

b) CaCO3 HNO3 →

Question 3: Give 2.19 grams of a mixture of Cu, Al completely working with excess

HNO3 solution, obtaining solution Y and 0.672 liters of NO gas (in the DCT, which is the only reducing product) Calculate the percentage by mass of two metals in the mixture?

TÀI LIỆU THAM KHẢO

1 Cao Cự Giác (Chủ biên), Trần Trung Ninh (2018) Phương pháp dạy học hoá học bằng tiếng Anh ở trường Trung học phổ thông Nxb Đại học Vinh.

2 Cao Cự Giác (2019) Dạy học một số chủ đề hoá học bằng tiếng Anh Nxb Giáo dục.