COPPER AND ITS COMPOUNDS
LESSON IN 11TH NATURAL SCIENCE CLASS
To increase the cognitive activity and independence of students, we use lessons for collective study of material. In such lessons, each student (or pair of students) receives a task, the completion of which he must report on in the same lesson, and his report is recorded by the rest of the class students in notebooks and is an element of the content of the lesson’s educational material. Each student contributes to the class's learning about the topic.
During the lesson, the students’ work mode changes from intraactive (a mode in which information flows are closed within the students, typical for independent work) to interactive (a mode in which information flows are two-way, i.e. information goes both from the student and to the student, information is exchanged). In this case, the teacher acts as the organizer of the process, corrects and supplements the information provided by the students.
Lessons for collective study of material consist of the following stages:
Stage 1 – installation, in which the teacher explains the goals and program of work for the lesson (up to 7 minutes);
Stage 2 – independent work of students according to instructions (up to 15 minutes);
Stage 3 – exchange of information and summing up the lesson (takes up all the remaining time).
The lesson “Copper and its compounds” is designed for classes with in-depth study of chemistry (4 hours of chemistry per week), is conducted over two academic hours, the lesson updates students’ knowledge on the following topics: “General properties of metals”, “Attitude towards metals with concentrated sulfuric acid” acid, nitric acid”, “Qualitative reactions to aldehydes and polyhydric alcohols”, “Oxidation of saturated monohydric alcohols with copper(II) oxide”, “Complex compounds”.
Before the lesson, students receive homework: repeat the listed topics. The teacher's preliminary preparation for the lesson consists of drawing up instruction cards for students and preparing sets for laboratory experiments.
DURING THE CLASSES
Installation stage
The teacher poses to the students the purpose of the lesson: based on existing knowledge about the properties of substances, predict, practically confirm, summarize information about copper and its compounds.
Students compose the electronic formula of the copper atom, find out what oxidation states copper can exhibit in compounds, what properties (redox, acid-base) copper compounds will have.
A table appears in the students' notebooks.
Properties of copper and its compounds
| Metal | Cu 2 O – basic oxide | CuO – basic oxide |
| Reducing agent | CuOH is an unstable base | Cu(OH) 2 – insoluble base |
| CuCl – insoluble salt | CuSO 4 – soluble salt | |
| Possess redox duality | Oxidizing agents |
Independent work stage
To confirm and supplement assumptions, students perform laboratory experiments according to the instructions and write down the equations of the reactions performed.
Instructions for independent work in pairs
1. Heat the copper wire in a flame. Notice how its color has changed. Place hot calcined copper wire in ethyl alcohol. Notice the change in its color. Repeat these manipulations 2-3 times. Check to see if the ethanol smell has changed.
Write down two reaction equations corresponding to the transformations carried out. What properties of copper and its oxide are confirmed by these reactions?2. Add hydrochloric acid to copper(I) oxide.
What are you observing? Write down the reaction equations, taking into account that copper(I) chloride is an insoluble compound. What properties of copper(I) are confirmed by these reactions?3. a) Place a zinc granule into a solution of copper(II) sulfate. If the reaction does not proceed, heat the solution. b) Add 1 ml of sulfuric acid to copper(II) oxide and heat.
What are you observing? Write down the reaction equations. What properties of copper compounds are confirmed by these reactions?4. Place a strip of universal indicator into the copper(II) sulfate solution.
Explain the result. Write down the ionic equation for hydrolysis in step I.
Add a solution of honey(II) sulfate to the sodium carbonate solution.
What are you observing? Write down the equation for the joint hydrolysis reaction in molecular and ionic forms.5.
What are you observing?
Add ammonia solution to the resulting precipitate.
What changes have occurred? Write down the reaction equations. What properties of copper compounds do these reactions prove?6. Add a solution of potassium iodide to copper(II) sulfate.
What are you observing? Write an equation for the reaction. What property of copper(II) does this reaction prove?7. Place a small piece of copper wire in a test tube with 1 ml of concentrated nitric acid. Close the test tube with a stopper.
What are you observing? (Take the test tube under the traction.) Write down the reaction equation.
Pour hydrochloric acid into another test tube and place a small piece of copper wire in it.
What are you observing? Explain your observations. What properties of copper are confirmed by these reactions?8. Add excess sodium hydroxide to copper(II) sulfate.
What are you observing? Heat the resulting precipitate. What happened? Write down the reaction equations. What properties of copper compounds are confirmed by these reactions?9. Add excess sodium hydroxide to copper(II) sulfate.
What are you observing?
Add glycerin solution to the resulting precipitate.
What changes have occurred? Write down the reaction equations. What properties of copper compounds do these reactions prove?10. Add excess sodium hydroxide to copper(II) sulfate.
What are you observing?
Add glucose solution to the resulting precipitate and heat.
What happened? Write down the reaction equation using the general formula of aldehydes to denote glucoseWhat property of the copper compound does this reaction prove?
11. Add to copper(II) sulfate: a) ammonia solution; b) sodium phosphate solution.
What are you observing? Write down the reaction equations. What properties of copper compounds do these reactions prove?
Stage of information exchange and summing up
The teacher asks a question regarding the properties of a particular substance. Students who performed the relevant experiments report on the experiment performed and write down the reaction equations on the board. Then the teacher and students add information about the chemical properties of the substance, which could not be confirmed by reactions in the school laboratory.
Procedure for discussing the chemical properties of copper compounds
1. How does copper react with acids, what other substances can copper react with?
The reaction equations for copper are written with:
Concentrated and diluted nitric acid:
Cu + 4HNO 3 (conc.) = Cu(NO 3) 2 + 2NO 2 + 2H 2 O,
3Cu + 8HNO 3 (diluted) = 3Cu(NO 3) 2 + 2NO + 4H 2 O;
Concentrated sulfuric acid:
Cu + 2H 2 SO 4 (conc.) = CuSO 4 + SO 2 + 2H 2 O;
Oxygen:
2Cu + O 2 = 2CuO;
Cu + Cl 2 = CuCl 2;
Hydrochloric acid in the presence of oxygen:
2Cu + 4HCl + O 2 = 2CuCl 2 + 2H 2 O;
Iron(III) chloride:
2FeCl 3 + Cu = CuCl 2 + 2FeCl 2.
2. What properties do copper(I) oxide and chloride exhibit?
Attention is drawn to the basic properties, the ability to form complexes, and redox duality. The equations for the reactions of copper(I) oxide with are written:
Hydrochloric acid until CuCl is formed:
Cu 2 O + 2HCl = 2CuCl + H 2 O;
Excess HCl:
CuCl + HCl = H;
Reduction and oxidation reactions of Cu 2 O:
Cu 2 O + H 2 = 2Cu + H 2 O,
2Cu2O + O2 = 4CuO;
Disproportionation when heated:
Cu 2 O = Cu + CuO,
2CuCl = Cu + CuCl 2 .
3. What are the properties of copper(II) oxide?
Attention is drawn to the basic and oxidative properties. The equations for the reactions of copper(II) oxide with are written:
Acid:
CuO + 2H + = Cu 2+ + H 2 O;
Ethanol:
C 2 H 5 OH + CuO = CH 3 CHO + Cu + H 2 O;
Hydrogen:
CuO + H 2 = Cu + H 2 O;
Aluminum:
3CuO + 2Al = 3Cu + Al 2 O 3.
4. What are the properties of copper(II) hydroxide?
Attention is drawn to oxidative, basic properties, the ability to form complexes with organic and inorganic compounds. Reaction equations are written with:
Aldehyde:
RCHO + 2Cu(OH) 2 = RCOOH + Cu 2 O + 2H 2 O;
Acid:
Cu(OH) 2 + 2H + = Cu 2+ + 2H 2 O;
Ammonia:
Cu(OH) 2 + 4NH 3 = (OH) 2;
Glycerin:
Decomposition reaction equation:
Cu(OH) 2 = CuO + H 2 O.
5. What properties do copper(II) salts exhibit?
Attention is drawn to the reactions of ion exchange, hydrolysis, oxidative properties, and complexation. The equations for the reactions of copper sulfate with:
Sodium hydroxide:
Cu 2+ + 2OH – = Cu(OH) 2 ;
Sodium phosphate:
3Cu 2+ + 2= Cu 3 (PO 4) 2;
Cu 2+ + Zn = Cu + Zn 2+ ;
Potassium iodide:
2CuSO 4 + 4KI = 2CuI + I 2 + 2K 2 SO 4 ;
Ammonia:
Cu 2+ + 4NH 3 = 2+ ;
and reaction equations:
Hydrolysis:
Cu 2+ + HOH = CuOH + + H + ;
Co-hydrolysis with sodium carbonate to form malachite:
2Cu 2+ + 2 + H 2 O = (CuOH) 2 CO 3 + CO 2.
In addition, you can tell students about the interaction of copper(II) oxide and hydroxide with alkalis, which proves their amphoteric nature:
Cu(OH) 2 + 2NaOH (conc.) = Na 2,
Cu + Cl 2 = CuCl 2,
Cu + HgCl 2 = CuCl 2 + Hg,
2Cu + 4HCl + O 2 = 2CuCl 2 + 2H 2 O,
CuO + 2HCl = CuCl 2 + H 2 O,
Cu(OH) 2 + 2HCl = CuCl 2 + 2H 2 O,
CuBr 2 + Cl 2 = CuCl 2 + Br 2,
(CuOH) 2 CO 3 + 4HCl = 2CuCl 2 + 3H 2 O + CO 2,
2CuCl + Cl 2 = 2CuCl 2,
2CuCl = CuCl 2 + Cu,
CuSO 4 + BaCl 2 = CuCl 2 + BaSO 4.)
Exercise 3. Make chains of transformations corresponding to the following schemes and carry them out:
Task 1.
An alloy of copper and aluminum was treated first with an excess of alkali and then with an excess of dilute nitric acid. Calculate the mass fractions of metals in the alloy if it is known that the volumes of gases released in both reactions (under the same conditions) are equal
.
(Answer . Mass fraction of copper – 84%.)
Task 2. When 6.05 g of copper(II) nitrate crystalline hydrate was calcined, 2 g of a residue was obtained. Determine the formula of the original salt.
(Answer. Cu(NO 3) 2 3H 2 O.)
Task 3. A copper plate weighing 13.2 g was dipped into 300 g of iron(III) nitrate solution with a salt mass fraction of 0.112. When it was taken out, it turned out that the mass fraction of iron(III) nitrate became equal to the mass fraction of the formed copper(II) salt. Determine the mass of the plate after it was removed from the solution.
(Answer. 10 years)
Homework. Learn the material written in the notebook. Make a chain of transformations for copper compounds, containing at least ten reactions, and carry it out.
LITERATURE
1. Puzakov S.A., Popkov V.A. A manual on chemistry for applicants to universities. Programs. Questions, exercises, tasks. Sample exam papers. M.: Higher School, 1999, 575 p.
2. Kuzmenko N.E., Eremin V.V. 2000 problems and exercises in chemistry. For schoolchildren and applicants. M.: 1st Federative Book Trading Company, 1998, 512 p.
The binary substance copper chloride (monochloride), whose formula is CuCl, is a salt of hydrochloric acid. This is a powder, usually white or green in color, very poorly soluble in water. The greenish tint of monochloride crystals is due to the presence of impurities of a divalent substance called copper chloride ii.
This compound was first obtained by the great chemist Robert Boyle. This event happened a long time ago, and to obtain it the scientist used simple metal copper and divalent. Then, in 1799, Joseph Proust isolated dichloride crystals from monochloride. This reaction was a process of gradually heating the solution, as a result of which copper (II) chloride lost some of its chlorine, about half of its presence. Separation of dichloride from monochloride was carried out by conventional washing.
Copper monochloride is a white crystalline substance that, at a temperature of 408 °C, changes the shape of the crystal lattice. Since this compound both melts and boils practically without decomposition, its chemical formula is sometimes written as Cu2Cl2. Monochloride, however, like other copper compounds, is toxic.
The copper chloride compound, whose formula is written as CuCl2, appears in appearance as dark brown wedge-shaped single crystals. When interacting with even a very small amount of water, the crystals of the compound change color: from dark brown it successively turns into greenish, and then into blue. It is interesting that if you add very little to such an aqueous solution, the crystals will return to one of the intermediate states - they will become greenish.
The melting point of the substance is 537 °C, and at a temperature of 954 - 1032 °C, it boils. The compound is soluble in substances such as water, alcohol, and ammonia. Its density is 3.054 g/cm3. With constant dilution of the solution and maintaining the temperature at 25 ° C, the molar electrical conductivity of the substance is 265.9 cm2/mol.
Copper chloride is obtained by the action of chlorine on copper, as well as by carrying out reaction reaction (II) with Industrial production is based on roasting mixtures of copper sulfides with sodium chloride. In this case, during the reaction process, a temperature of 550-600 ° C must be ensured, as a result of which, in addition to the substance itself, the presence in the gaseous state of such components as HCl, sulfur gases and arsenic compounds is detected. There are known productions where the production of copper chloride is carried out by initiating an exchange reaction between copper sulfate and BaCl2.
At a temperature of 993 °C, the substance decomposes into CuCl and Cl2, its solubility in aqueous solutions is characterized by:
When dissolved in an aqueous solution at a temperature of 25 degrees, 77.4 grams of copper chloride completely dissolves in 100 grams of water;
When the temperature of the solution reaches 100 °C, 120 grams of the substance already dissolve in it. In both cases, it is assumed that the density of CuCl2 was the same.
Copper chloride is widely used as a chemical catalyst, a component of pyrotechnic mixtures, and in the production of various mineral dyes. As used as a flue gas analyzer, it helps to calculate flue gas concentration and carbon dioxide levels. Dichloride is also used as an oxygen carrier at various stages of chemical production; this technology, for example, is common in the production of organic dyes.
The copper chloride salt, despite its insoluble solubility, is capable of forming a number of crystalline hydrates. In this case, a concentrated solution of the substance has the ability to add nitric oxide, which is also widely used in the production of medicines and in the chemical industry.
Copper chloride 2
Chemical properties
The product is a binary inorganic substance and belongs to the class salts And halides . It can be considered as a salt formed hydrochloric acid And copper .
Racemic formula of Copper Chloride: CuCl2.
Molecular weight of this compound = 134.5 grams per mole. The substance melts at 498 degrees Celsius. The product forms crystalline hydrates of the form CuCl2 nH2O .
Used in medicine Copper Chloride Dihydrate.
The product in solid form is yellow-brown crystals. Compound crystalline hydrates depends on the temperature at which crystallization occurs. The substance is highly soluble in ethyl alcohol, water, acetone And methanol .
Copper Chloride Reactions
The substance interacts with alkali , thus, as a rule, an insoluble base and a soluble salt are formed. Copper Chloride reacts with metals that are located to the left of the metal in the electrochemical series Cu . Also, the compound is characterized by reactions ion exchange with other salts, resulting in the formation of an insoluble substance and the release of gas.
On an industrial scale, the agent is obtained by the reaction Copper oxide 2 with hydrochloric acid or by exchange reaction Barium chloride With Copper sulfate .
There is also a connection Copper chloride 1 , in which copper is monovalent. Monochloride this metal is a rather toxic compound.
pharmachologic effect
Metabolic.
Pharmacodynamics and pharmacokinetics
Copper is essential for the body. For example, it takes part in a number of chemical reactions occurring in liver tissue. After entering the body, the substance is almost completely metabolized.
Indications for use
Copper Chloride solution is included in solutions used for parenteral nutrition , and satisfies the body's need for microelements .
Contraindications
Drugs that contain a solution cannot be used if the patient is sensitive to the substances in the composition, for children under 10 years of age. Caution should be exercised in case of renal or hepatic insufficiency.
Side effects
Usually the medicine is well tolerated by patients. Rarely, nausea and pain at the injection site occur during infusion.
Copper chloride, instructions for use (Method and dosage)
The drug is administered intravenously.
If the drug is initially in powder form, it is diluted in solutions glucose or .
The resulting solution must be used within 24 hours.
The dosage regimen and treatment regimen depend on the drug and the disease.
Overdose
Overdose of the drug occurs rarely. Most often it is used under medical supervision. staff and in the hospital.
If the drug is administered too quickly, the following may occur: vomiting, sweating, hyperemia skin. The reactions disappear after reducing the rate of drug administration.
Interaction
You can mix the substance in one syringe or bag only with solutions glucose or amino acids , the concentration of which does not exceed 50%.
During pregnancy and lactation
The drug can be prescribed to pregnant women.
There is insufficient data on the use of this component during breastfeeding.
Drugs containing (Analogs)
Level 4 ATX code matches:Copper Chloride is included in the form of dihydrate in the composition of the concentrate for the preparation of solutions for infusions Addamel N.
General information about the hydrolysis of copper (II) chloride
DEFINITION
Copper(II) chloride– a medium salt formed by a weak base – copper (II) hydroxide (Cu(OH) 2) and a strong acid – hydrochloric (hydrochloric) (HCl). Formula - CuCl 2.
Represents crystals of yellow-brown (dark brown) color; in the form of crystalline hydrates - green. Molar mass – 134 g/mol.
Rice. 1. Copper(II) chloride. Appearance.
Hydrolysis of copper(II) chloride
Hydrolyzes at the cation. The nature of the environment is acidic. Theoretically, a second stage is possible. The hydrolysis equation is as follows:
First stage:
CuCl 2 ↔ Cu 2+ + 2Cl - (salt dissociation);
Cu 2+ + HOH ↔ CuOH + + H + (hydrolysis by cation);
Cu 2+ + 2Cl - + HOH ↔ CuOH + + 2Cl - + H + (ionic equation);
CuCl 2 + H 2 O ↔ Cu(OH)Cl +HCl (molecular equation).
Second stage:
Cu(OH)Cl ↔ CuOH + + Cl - (salt dissociation);
CuOH + + HOH ↔ Cu(OH) 2 ↓ + H + (hydrolysis by cation);
CuOH + + Cl - + HOH ↔ Cu(OH) 2 ↓ + Cl - + H + (ionic equation);
Cu(OH)Cl + H 2 O ↔ Cu(OH) 2 ↓ + HCl (molecular equation).
Examples of problem solving
EXAMPLE 1
EXAMPLE 2
| Exercise | Write down the equation for the electrolysis of a solution of copper (II) chloride. What mass of substance will be released at the cathode if 5 g of copper (II) chloride is subjected to electrolysis? |
| Solution | Let us write the dissociation equation for copper (II) chloride in an aqueous solution: CuCl 2 ↔ Cu 2+ +2Cl - . Let us conventionally write down the electrolysis scheme: (-) Cathode: Cu 2+, H 2 O. (+) Anode: Cl - , H 2 O. Cu 2+ +2e → Cu o ; 2Cl - -2e → Cl 2. Then, the electrolysis equation for an aqueous solution of copper (II) chloride will look like this: CuCl 2 \u003d Cu + Cl 2. Let's calculate the amount of copper (II) chloride using the data specified in the problem statement (molar mass - 134 g/mol): υ(CuCl 2) = m(CuCl 2)/M(CuCl 2) = 5/134 = 0.04 mol. According to the reaction equation υ(CuCl 2) = υ(Cu) =0.04 mol. Then we calculate the mass of copper released at the cathode (molar mass – 64 g/mol): m(Cu)= υ(Cu)×M(Cu)= 0.04 ×64 = 2.56 g. |
| Answer | The mass of copper released at the cathode is 2.56 g. |
Basic information:
| Protective, prohibiting fungal spores and pathogens from entering leading tissues |
| Corona yellow body (anhydrous) to blue-green crystals (dihydrate) |
Release:
copper chloride: behavior in the environment
| Index | Meaning | Explanation | ||
| Solubility in water at 20 o C (mg/l) | 757000 Q4 High||||
| Solubility in organic solvents at 20 o C (mg/l) | 680000 Q4 - Methanol -||||
| Melting point (o C) | - - -||||
| Boiling point (o C) | - - -||||
| Decomposition temperature (o C) | - - -||||
| Flash point (o C) | - - -||||
| Partition coefficient in the octanol/water system at pH 7, 20 o C | P: - - -||||
| Specific Gravity (g/ml) / Specific Gravity | 3.39 Q3 -||||
| Dissociation constant (pKa) at 25 o C | - - -||||
| Note: | ||||
| Vapor pressure at 25 o C (MPa) | 1.00 X 10 -10 Q1 Not volatile||||
| Henry's law constant at 25 o C (Pa*m 3 /mol) | - - -||||
| Henry's law constant at 20 o C (dimensionless) | 7.29 X 10 -21 Calculated Not volatile||||
| Decay period in soil (days) | DT50 (typical) - - -||||
| - | ||||
| Aqueous photolysis DT50 (days) at pH 7 | Meaning: - - -||||
| - | ||||
| Aqueous hydrolysis DT50 (days) at 20 o C and pH 7 | Meaning: - - -||||
| - | ||||
| Water deposition DT50 (days) | - - -||||
| Only aqueous phase DT50 (days) | - - -||||
| Potential leaching index GUS | - - -||||
| Concentration growth index in groundwater SCI (µg/l) at an application dose of 1 kg/ha (l/ha) | Meaning: - - -||||
| - | ||||
| Potential for particle bound transport index | - - -||||
| Koc - organic carbon distribution coefficient (ml/g) | - - -||||
| pH stability: | ||||
| Note: | ||||
| Freundlich adsorption isotherm | Kf: -- | -|||
| - | ||||
| Maximum UV absorption (l/(mol*cm)) | - - -||||
copper chloride: ecotoxicity
| Index | Meaning | Source / Qualitative indicators / Other information | Explanation | |
| Bioconcentration factor | BCF: -- | -|||
| Bioaccumulation potential | - - -||||
| LD50 (mg/kg) | 140 V3 Rat Moderate||||
| Mammals - Short-term food NOEL | (mg/kg): -- | -|||
| Birds - Acute LD50 (mg/kg) | - - -||||
| Birds - Acute toxicity (CK50/LD50) | - - -||||
| Fish - Acute 96 hour CK50 (mg/l) | 0.24 F4 Rainbow trout Moderately||||
| Fish - Chronic 21 day NOEC (mg/l) | - - -||||
| Aquatic invertebrates - Acute 48 hour EC50 (mg/l) | - - -||||
| Aquatic Invertebrates - Chronic 21 day NOEC (mg/L) | - - -||||
| Aquatic crustaceans - Acute 96 hour CK50 (mg/l) | 0.134 F3 Mysis shrimp Moderately||||
| Bottom microorganisms - Acute 96 hour CK50 (mg/l) | 0.043 F4 Chironomus mosquito High||||
| NOEC , static, Water (mg/l) | - - -||||
| Benthic microorganisms - Chronic 28 day NOEC, Sediment (mg/kg) | - - -||||
| Aquatic plants - Acute 7 day EC50, biomass (mg/l) | - - -||||
| Algae - Acute 72 hour EC50, growth (mg/l) | 0.55 H1 Unknown species Moderate||||
| Algae - Chronic 96 hour NOEC, growth (mg/l) | - - -||||
| Bees - Acute 48 hour LD50 (µg/individual) | - - -||||
| Soil worms - Acute 14-day CK50 (mg/kg) | - - -||||
| Soil worms - Chronic 14-day maximum non-active concentration of the substance, reproduction (mg/kg) | 15 A4 Earthworm, as Cu, 8 week Moderate||||
| Other Arthropods (1) | LR50 (g/ha): - - -||||
| Other Arthropods (2) | LR50 (g/ha): - - -||||
| Soil microorganisms | - - -||||
| Available data on the mesoworld (mesocosm) | NOEAEC mg/l: - - -||||
copper chloride: human health
Basic indicators:
| Index | Meaning | Source / Qualitative indicators / Other information | Explanation | |
| Mammals - Acute oral LD50 (mg/kg) | 140 V3 Rat Moderate||||
| Mammals - Dermal LD50 (mg/kg body weight) | - - -||||
| Mammals - Inhalation | ||||
