Independent work in organic chemistry on the topics:

Alkanes, Alkenes, Alkynes.

Chemistry teacher Zhuravleva T.K.

Independent work on the topic: Alkanes

Option number 1

1. Correlate:

Concept:

1) homologues, 2) isomers.

Definition:

a) substances similar in structure and properties, the composition of which differs by one or more CH 2 groups.

b) substances having the same composition but different chemical structure.

2. General formula alkanes

a) C n H 2 n -6, b) C n H 2 n -2, c) C n H 2 n, d) C n H 2 n +2.

3.

a) C 2 H 8, b) C 2 H 6, c) C 5 H 8, d) C 6 H 6.

Name this substance, write its full structural formula.

4. Find the formula for the isomer of pentane:

a) CH 3 -CH-CH 3, b) CH 3 -CH 2, c) CH 2 -CH 2 d) CH 3 -CH 2

│ │ │ │ │

CH 3 CH 3 CH 3 CH 3 CH-CH 3

5. Substances that are homologues are:

a) C 3 H 8 and C 2 H 2, b) C 5 H 12 and C 3 H 6, c) C 2 H 2 and C 6 H 6, d) CH 4 and C 2 H 6

6. Alkanes are characterized by reactions:

a) addition b) substitution c) polymerization.

7. Correlate:

Alkane formula :

1) CH 3 -CH 2 -CH 2 -CH 2 2) CH 3 -CH 2 -CH 2 -CH 2

CH 3 CH 3 CH 2 - CH 3

Name:

a) 2-methylpentane, b) hexane

Option number 2

1. Insert the missing word:

a) Substances that are similar in structure and properties, the composition of which differs by one or more CH 2 groups, are called -___. b) Substances that have the same elemental composition but different chemical structure are called _________.

2. Limit hydrocarbons have the general formula:

a) C n H 2 n -6, b) C n H 2 n -2, c) C n H 2 n, d) C n H 2 n +2

3. Specify the formula of limiting hydrocarbon:

a) C 2 H 4, b) C 3 H 4, c) C 4 H 10, d) C 6 H 6.

4. Find the formula for butane homologue:

a) CH 3 -CH 2, b) CH 3 -CH 2 -CH-CH 3, c) CH 3 -CH 2 -CH 2 -CH 3

CH 2 -CH 2 -CH 3 CH 3

d) CH 3 -CH -CH 3

5. Homologues are substances of normal structure:

a) CH 4 and C 2 H 4, b) C 3 H 8 and C 5 H 12, c) C 4 H 8 and C 8 H 1 8, d) CH 4 and C 6 H 10

6. Compose the formulas for the isomer and homologue of hexane

7. Match:

Alkane formula: 1) CH 3 -CH 2 -CH-CH 2 CH 2 -CH 3 2) CH 3 -CH 2 - CH-CH-CH 3

C 2 H 5 CH 3 CH 3

Name:

a) 3-ethylhexane, b) 2,3-dimethylpentane

Independent work on the topic: Alkenes.

Option number 1

a) a homologue; b) isomer;

CH 2 \u003d CH - CH - CH 2 - CH 2 - CH 3

CH 3

CH 3 |

a) CH 3 - CH \u003d C - CH - CH 3 b) CH 2 \u003d C - CH 2 - CH - CH 3

׀ ׀ ׀

CH 3 CH 3 CH 2 - CH 3

3.Get alkene by dehydrogenating butane.

4. Write equations chemical reactions and indicate the type of reactions:

a) CH 2 \u003d CH - CH 3 + H 2 →

b) CH 3 - CH \u003d CH - CH 3 + Br 2 →

c) C 2 H 4 + O 2 →

d) CH 2 \u003d CH -CH 2 + HCl →

Option number 2

1. Make structural formulas:

a) a homologue; b) isomer;

c) isomer of the position of the double bond.

for a substance that has the structure

CH 3 - CH \u003d CH - CH - CH 3

C 2 H 5

2. Name the following hydrocarbons according to the systematic nomenclature:

CH 3

a) CH 2 \u003d C - CH 2 - CH 2 b) CH 3 - CH \u003d C - C - CH 3

׀ ׀ ׀

CH 3 CH 3 CH 3

3.Get propene by alcohol dehydration.

4. Write the equations of chemical reactions and indicate the type of reaction:

a) CH 2 \u003d CH - CH 2 - CH 3 + H 2 O →

b) CH 2 \u003d CH 2 + H 2 →

c) CH 2 \u003d CH 2 + HCL →

d) C 3 H 6 + O 2 →

Independent work

Yurgamysh branch

GBPOU "Kurgan Basic Medical College»

Collection independent work in chemistry

under the section "Unsaturated hydrocarbons"

for the specialty 34.02.01 "Nursing"

compiled by a chemistry teacher: N.S. Trofimova

Yurgamysh 2017

Independent work

"Alkenes. Composition, structure. Isomerism and nomenclature.

Physical and chemical properties. Relationship with alkanes»

1. Specify the general formula of alkenes and the general formula of alkanes.

2. Make structural formulas for the following substances:

3-methylbutene-1

2-methylbutene-1

2,2-dimethylpropane

3. Name the hydrocarbons: A) CH 2 \u003d CH-CH 2 -CH (CH 3) 2 B) (CH 3) 2 CH-C (CH 3) \u003d CH-CH 2 - CH 3

4. Write the structural formula of the 2-methylpentene-1 isomer.

5. Write down the structural formula of any butene-1 homologue.

6. What types of isomerism are characteristic of alkenes? Make up the formulas: A) trans-butene-1

B) cis-1-bromopropene

7. Indicate the hydrogenation reaction

C 2 H 4 + H 2 → C 2 H 6

C 2 H 4 + H 2 O → C 2 H 5 OH

C 2 H 6 → C 2 H 4 + H 2

C 2 H 4 + Cl 2 → C 2 H 6 Cl 2

8. Why addition reactions are typical for alkenes, while such reactions are generally impossible for alkanes.

9. Indicate the correct judgment: A) Markovnikov's rule - when a hydrogen halide is added to an alkene, hydrogen is attached to the carbon atom with a double bond, to which a greater number of hydrogen atoms are connected; B) a polymer is a high-molecular compound, the molecules of which consist of many identical structural units.

10. Gas was obtained in the laboratory. In order to establish its structure, it was passed through a yellow solution of bromine. The solution became colorless. What hydrocarbons can be attributed to the resulting gas and why?

_____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

11. Violet potassium permanganate solution can be discolored with

Support your answer with the reaction equation.

12. Solve the scheme:

Na? ? + H 2 O + O 2

chloroethane → butane → chlorobutane → butene-1 → А → ?

14. Make a polymerization reaction involving butene-2.

15. Give an equation for a chemical reaction that demonstrates Markovnikov's rule.

Option 1

Write the equation for the reaction of obtaining 2-methylbutene-2 ​​by dehydration of the corresponding alcohol and dehydrohalogenation of the haloalkane.

CH 3 -CH 2 -CH 2 OH → CH 2 \u003d CH-CH 3 → CH 3 -CHCl-CH 3 → CH 3 -CH (CH 3) -CH (CH 3) -CH 3 → CH 3 -C (CH 3) \u003d C (CH 3) -CH 3

What is the structural formula of ethylene hydrocarbon if 11.2 g of it, upon interaction with an excess of HBr, turns into 27.4 g of bromoalkane with the halogen position at the tertiary carbon atom?

Independent work on the topic "Alkenes"

Option 2

Write the equation for the reaction of obtaining 2,3-dimethylbutene-1 by dehydration of the corresponding alcohol and dehydrohalogenation of a haloalkane.

What reactions can be used to carry out the following transformations? Specify reaction conditions, if necessary.

C 6 H 12 → C 6 H 14 → C 3 H 6 → [-CH 2 -CH (CH 3) -] p

An ethylene hydrocarbon weighing 7.0 g decolorizes 640 g of bromine water with a mass fraction of bromine of 2.5%. Determine the molecular formula of alkene.

Card 1. Topic: Alkenes 1. To classalkenes applies 1) C 2 H 6 2) C 3 H 4 3) C 2 H 4 4) C 5 H 12 2. Alkenes are characterized by isomerism 1) carbon skeleton 2) geometric 3) double bond positions 4) interclass water in the combustion reaction of ethylene 4. As a resulthydrochlorination butene-1 is formed 1) 1-chlorobutane 2) 2-chlorobutane 3) 1-chlorobutene-1 4) 2-chlorobutene-1 5) Ethylene can be obtained by the reaction 1) alcohol dehydration 2) alkane dehydrogenation 3) cracking 4) polymerization

Card 2. Topic: Alkenes 1. Alkene, whose molecule contains 6 carbon atoms, has the formula 1) C 6 H 14 2) C 6 H 12 3) C 6 H 10 4) C 6 H 6 2. The isomer of pentene-1 is 1) 2-methylbeten - 1 2) cyclopentane 3) pentene-3 4) pentene-2 3. Coefficient before the formulawater in the combustion reaction of propene 4. As a resulthydration butene-1 is formed 1) butanol-1 2) butanol-2 3) 1-methylbutene-1 4) 2-methylbutene-1 5. Qualitative reaction on alkenes is 1) hydrogenation 2) burning 3) bromination 4) oxidation with potassium permanganate

Card 3. Topic: Alkenes 1. To classalkenes applies 1) C 5 H 12 2) C 7 H 14 3) C 6 H 10 4) C 7 H 16 2. How many isomers can exist for a substance with composition C 4 H 8 ? 3. Coefficient before the formulawater in the butene combustion reaction 4. As a result of the addition of hydrogen bromide to butene-1 is formed 1) 1-bromobutane 2) 2-bromobutane 3) 1-bromobutene-1 4) 2-bromobutene-1 5. You can get propene by reaction 1) butane hydrogenation 2) propyne hydration 3) propane dehydrogenation 4) hydrogenation of ethene

Card 4. Topic: Alkenes 1. Compositionalkenes reflects the general formula 1) C n H 2n+2 2) C n H 2n 3) C n H 2n-2 4) C n H 2n-6 2. The isomer of cis-butene-2 ​​is 1) methyl propane 2) trans-beten-2 3) methylcyclopropane 4) cyclobutane 3. Coefficient before the formulawater in the combustion reaction of pentene 4. As a result addition of hydrogen chloride to pentene-1 is formed 1) 1-chloropentane 2) 2-chloropentane 3) 1-chloropentene-1 4) 2-chloropentene-1 5. When ethylene is oxidized with potassium permanganate, 1) carbon dioxide 4) ethylene glycol

This work was offered to students in order to control the assimilation of program material on unsaturated hydrocarbons (alkynes and alkenes) and tasks: check the level of assimilation of nomenclature and isomerism, the ability to obtain alkenes and alkynes, draw up reaction equations with their participation, solve qualitative and computational problems on these topics.

The work is compiled taking into account the individual approach:

Option 1 - lightweight;

Option 2 - medium level;

Option 3 - complicated.

Test

1 task

1 option.

What is the number of isomeric alkenes of composition C 5 H 10? Make up their formulas and name them.

Option 2.

Make formulas of isomers for the proposed substance, name them, indicate the types of isomerism. 2,5-dimethylhexine-3

3 option.

Which of the following pairs of substances are isomers?

Name the substances, indicate the types of isomerism.

2 task

1 option .

Make up the reaction equations, name all the substances.

Option 2.

Carry out transformations, indicate the names of substances, types of chemical reactions, conditions for their implementation:

3 option.

Given a chain of transformations:

Carry out transformations, name the substances, indicate the types of reactions.

3 task

1 option

How to recognize the following substances: ethane, ethene, ethine?

Write reaction equations.

Option 2.

Suggest a method for recognizing compounds: butane, butene - 1, propyne.

Write reaction equations.

3 option.

Suggest a way to recognize substances: propane, pentene - 2, pentine - 2, pentine - 1.

Write reaction equations.

4 task

A task.

1 option

How many liters of hydrogen will be required for the complete hydrogenation of 16.2 g of butyne - 2?

Option 2

What mass of calcium carbide containing 15% impurities must be taken to obtain 40 liters of acetylene (n.o.)?

3 option

Carbon dioxide obtained by burning 8.4 liters of ethylene (N.O.) passed through 472 ml of 6% NaOH solution (density = 1.06 g / ml). What is the composition of the resulting salt and what is its mass fraction in solution?

Independent work on the topic "ALKYNE".

1. For the compound 6-methylheptin-3, write down the formulas of two homologues and 2 isomers.

2. Write down the reactions:

 Hydration of acetylene

 Hydrogenation of 4-methylpentine-2

 Burning propyne

 Halogenation of 2,5-dimethylhexine-3

 Bromination of butin-1

 Hydrogenation of 2,2,5-trimethylhexine-3

 Hydrogen halide addition to propyne

 Polymerization of acetylene

 Dehydrogenation of methane

 Ethylene dehydrogenation

8. What is formed by the action of an alcoholic solution of alkali on 2,3-dibromoethane.

Write an equation for the reaction.

9. Implement the chain:

Methane----ethylene----acetylene-----acetic aldehyde

1,2-dibromoethylene

10. Calculate the volume of acetylene that can be obtained from 130 g of calcium carbide,

Independent work on the topic “Alkadienes. Alkiny"

Option number 1.

Compose the electronic and structural formula of the propyne molecule, determine the valency and art. oxidation of carbon atoms. Indicate the hybridization state of the carbon atom in the triple bond.

For the example of the fifth member of the homologous series of alkynes, write the structural formulas:

a) 2 isomers of the position of the triple bond;

c) 2 isomers from another homologous series. Name all isomers.

Perform transformations:

C 2 H 5 COONa C 2 H 6 C 2 H 4 C 2 H 2 X

When burning 4.1 g of hydrocarbon, 13.2 g of carbon monoxide (IV) and 4.5 g of water were obtained. The hydrogen vapor density of the substance is 41. Determine the formula of the substance.

_______________________________________________________________________

Option number 2.

Compose the electronic and structural formula of the 2,3-dimethylbutadiene-1 molecule, determine the valency and art. oxidation of carbon atoms. Indicate the hybridization state of the carbon volume at the double bond.

Using the example of the sixth member of the homologous series of alkadienes, write the structural formulas:

a) 2 isomers of the position of bonds;

b) 2 isomers of the carbon chain;

c) cis- and trans-isomers;

d) 2 isomers from another homologous series. Name all isomers.

3. Perform transformations:

C 2 H 2 C 2 H 4 C 2 H 5 Br C 2 H 4 polymer

4. When burning 2.8 g of hydrocarbon, 0.2 mol carbon dioxide and 0.2 mol of water. 3.64 g of this substance occupies a volume of 1.456 liters (N.O.). Determine the molecular formula of the substance.

Tests on the topic “Alkadienes. Alkiny"

1 .Pentin corresponds to the general formula:

a) C n H 2 n -6; b) C n H 2 n -2; c) C n H 2 n; d) C n H 2 n +2

2 . The carbon-carbon bond length is the shortest in a molecule:

a) C 2 H 4 b) C 2 H 2 c) C 4 H 10 d) C 5 H 10.

3 . A hydrocarbon in which the orbitals of all carbon atoms are sp-hybridized:

a) propadiene; b) propyne, c) ethyne, d) butadiene - 1.3.

4. Pentadiene - 1.4 and 2-methylbutadiene -1.3 are:

a) homologues, b) the same substance, c) geometric isomers, d) structural isomers.

5 . Limit hydrocarbons do not differ from unsaturated:

a) the type of hybridization, b) solubility in water, c) the presence of different connections between carbon atoms, d) the structure of molecules.

6 . The hydration reaction is:

a) ethylene, butyne-2, propadiene; b) propylene, pentane, ethine;

c) butadiene -1.3, butane, cyclopropane; d) ethene, ethane, ethine.

7 . Interact with potassium permanganate:

a) methane, ethyne, propene; b) propadiene, 2-chloropropane, propene;

c) propyne, butene-2, butadiene-1.3 d) cyclopentane, ethyne, ethene.

8 . Acetylene does not interact with:

a) bromine water, b) hydrogen bromide,

c) ammonia solution of silver oxide (I), d) nitrogen.

9 . Pentin-1 and 2-methylpentadiene-1,3 can be recognized:

a) an alcoholic solution of sodium hydroxide, b) bromine water,

c) concentrated nitric acid, d) ammonia solution of silver oxide (I).

10 . Bromine water becomes colorless under normal conditions:

a) methane, ethene, ethyne, b) propyne, butadiene-1,3, cyclohexane,

c) butadiene-1,3, ethene, propyne, d) butane, butene-1, ethine.

11. Pentin-1 and Pentin-2 can be recognized:

a) potassium permanganate solution, b) bromine water, c) hydrogen chloride solution,

d) ammonia solution of copper (I) chloride.

12 . The volume of a portion of propyne (n.o.), containing 6 * 10 23 hydrogen atoms, is:

a) 22.4 l, b) 5.6 l, c) 7.5 l, d) 11.2 l.

13 . For welding and cutting metals, a gas is used in which the mass fraction of carbon and hydrogen is 92.31 and 7.69%, respectively. This is gas:

a) ethane, b) ethylene, c) acetylene, d) methane.

14 . For complete hydrogenation of 7.8 g of acetylene, hydrogen with a volume (N.O.) ... .. (l) is required.

15. When processing 10 g of a sample of calcium carbide with water, 2.24 liters of acetylene were obtained. The mass fraction of calcium carbide in the sample is ....(%).

16 . From 1,2-dichloropropane weighing 62.15 g, 10 l (N.O.) of propyne was obtained. The practical yield is….. (%).

unsaturated hydrocarbons.

Alkenes

GRADE 10

This lesson is a lesson in studying new material in the form of a lecture with elements of conversation and independent work of students.
The students work in three groups. In each group, there is an assistant teacher who distributes work to each student in this group. Each student has a note.

REMINDER

Planned learning outcomes

Know: definition of unsaturated hydrocarbons of the ethylene series, the general formula of alkenes, four types of isomerism of alkenes, their physical and chemical properties, methods of obtaining and applications of hydrocarbons of the ethylene series.

Be able to: explain the features of the formation of - and - bonds, write down molecular, structural and electronic formulas alkenes, designate the distribution of electron density in the molecule, name the substances of the ethylene series according to the systematic nomenclature and write down their formulas by the names of the substances, formulate the formulas of various isomers according to the molecular formula of the alkene, write down the reaction equations that characterize the chemical properties of alkenes, compare the properties of alkenes with the properties of saturated hydrocarbons, solve problems to find the molecular formula.

Goals. Educational: learn to derive the general formula of alkenes, know their physical and chemical properties, be able to write down the molecular and structural formulas of alkenes, name substances according to systematic nomenclature, develop skills in solving problems to find the molecular formula.
Educational: to cultivate the desire to study actively, with interest, to instill conscious discipline, clarity and organization in work, to work under the motto: "One for all, and all for one."

Methods and methodological techniques lesson

• Individual work with cards.
• Work in groups and in pairs.
• Demonstration chemical experiment.
• Use of technical teaching aids.
• Independent work on formulating substances.
• Oral responses at the blackboard.
• Note-taking of material in a notebook according to the textbook.

Lesson Plan

(written on the board)

1. The structure of the ethylene molecule C 2 H 4.
2. Isomerism and nomenclature of alkenes.
3. Obtaining alkenes.
4. Physical properties.
5. Chemical properties.
6. Application.
7. Genetic connection.

Equipment and reagents. Cards with tasks, a graph projector and transparencies, a tripod, a device for receiving and collecting gases, a spirit lamp, test tubes, sand, a chemical spoon; ethyl alcohol, potassium permanganate, bromine water, sulfuric acid (conc.).

DURING THE CLASSES

The lesson begins with a conversation in the form frontal survey. The purpose of this part of the lesson is to create a "success situation." Students understand the questions, they know the answers to them and are actively involved in the work.

1. What is the link length?

(The bond length is the distance between the centers
nuclei of bonded atoms in a molecule.)

2. What can be said about the length of the carbon-carbon bond of substances with single (C–C) and double (C=C) bonds?

(The length of the carbon-carbon single bond is 0.154 nm
double bond - 0.133 nm, the double bond is stronger and shorter than the single.)

3. How many bonds can form between atoms?

4. What can be said about the strength of the bond?

(It is less durable than single - connection.)

5. Which chemical bond formed between hybridized clouds?

6. How many valence electrons does a carbon atom have?

Independent work.
Derivation of the molecular formula

A task. In the compound, the mass fraction of carbon is 85.7%, the mass fraction of hydrogen is 14.3%, the hydrogen density is 14. Derive the molecular formula of hydrocarbon.
(One of the students decides at the blackboard.)

Given:

(C) = 85.7% (or 0.857),
(H) = 14.3% (or 0.143),
D(H 2) = 14.

Find:

C x H y .

Solution

M(C x H y) = 14 2 = 28 g/mol.
For 1 mol C x H y m(C x H y) = 28 g,
m(C) = 28 (g) 0.857 = 24 g,
n(C) \u003d 24 (g) / 12 (g / mol) \u003d 2 mol,
m(H) \u003d 28 (g) 0.143 \u003d 4 g,
n(H) \u003d 4 (g) / 1 (g / mol) \u003d 4 mol.
The hydrocarbon formula is C 2 H 4.

We conclude that the C 2 H 4 molecule is not saturated with hydrogen atoms.

The structure of the ethylene molecule C 2 H 4

We demonstrate a model of a given hydrocarbon molecule through a graph projector.

The C 2 H 4 molecule is flat, the carbon atoms forming a double bond are in the state
sp 2-hybridization, bond angle 120°.

We compose a homologous series: C 2 H 4, C 3 H 6, C 4 H 8 ... and derive the general formula C n H2 n .
Let's sum up the stage.

Isomerism and nomenclature of alkenes

Types of isomerism
1) Consider the structural formulas of linear and branched alkenes having the same molecular formula C 4 H 8:

This type of isomerism is called isomerism of the carbon skeleton.

2) Multiple bond position isomerism:

3) Isomerism of different homologous series. General formula C n H2 n corresponds to two homologous series: alkenes and cycloparaffins. For example, the formula C 4 H 8 may belong to compounds of different classes:

4) Spatial or geometric isomerism. In butene-2 ​​CH 3 -CH \u003d CH -CH 3, each carbon in the double bond has different substituents (H and CH 3). In such cases, cistransisomerism is possible for alkenes. If the elements of the main carbon chain are on the same side of the double bond in the plane of the molecule, then this cisisomer; if on opposite sides, then this trans isomer:

Independent work on cards (5 min)
Name substances.

1st group:

2nd group:

3rd group:

The completed independent work is recorded on film and projected through a graph projector onto the screen. Students exercise self-control.

Obtaining alkenes

1) Dehydration of alcohols (demonstration experiment for obtaining ethylene from ethyl alcohol):

2) Dehydrogenation of alkanes:

3) Pyrolysis and cracking of oil and natural gas:

4) From halogenated alkanes:

Physical properties

Alkenes - ethene, propene and butene - under normal conditions (20 ° C, 1 atm) - gases, from C 5 H 10 to C 18 H 36 - liquids, higher alkenes - solids. Alkenes are insoluble in water, soluble in organic solvents.

Chemical properties

In organic chemistry, three types of chemical reactions are considered: substitution, addition, and decomposition.

1) Alkenes are characterized addition reactions.

Hydrogen addition (hydrogenation):

Addition of halogens (laboratory experiment on decolorization of bromine water):

Addition of hydrogen halides:

Markovnikov's rule: hydrogen is added at the site of a multiple bond to a more hydrogenated carbon, and halogen to a less hydrogenated one.

For example:

The reaction proceeds according to the ionic mechanism.

Accession of water (hydration reaction):

2) Oxidation reactions.

Demo Experience. Ethene decolorizes the potassium permanganate solution, which proves the unsaturated nature of ethene:

Ethylene glycol is used as an antifreeze, lavsan fiber, explosives are obtained from it.

The oxidation of ethene on a silver catalyst gives ethylene oxide:

Ethylene oxide is used to produce acetaldehyde, detergents, varnishes, plastics, rubbers and fibers, and cosmetics.

3) polymerization reaction.

The process of combining many identical molecules into larger ones is called the polymerization reaction.

Determine the molecular formula of a hydrocarbon that contains 85.7% carbon and has a hydrogen density of 21.

Given:

(C) = 0.857 (or 85.7%),
D(H 2) = 21.

Find:

Solution

M(C x H y) = D(H2) M(H 2) \u003d 21 2 \u003d 42 g / mol.
For n(C x H y) = 1 mol m(C) = 42 0.857 = 36 g,
n(C) \u003d 36 (g) / 12 (g / mol) \u003d 3 mol,
m(H) \u003d 42 - 36 \u003d 6 g,
n(H) \u003d 6 (g) / 1 (g / mol) \u003d 6 mol.
The formula of the hydrocarbon is C 3 H 6 (propene).

Task 3.When 4.2 g of the substance is burned, 13.2 g of carbon monoxide (IV) and 5.4 g of water are formed. The vapor density of this substance in air is 2.9. Determine the composition of the hydrocarbon molecule.

Given:

m(C x H y) = 4.2 g,
m(CO 2) \u003d 13.2 g,
m(H 2 O) \u003d 5.4 g,
D(air) = 2.9.

Find: C x H y .

Solution

M(C x H y) = 2.9 29 = 84 g/mol.
To solve the problem, we write the reaction equation:

Let's find the mass X mole of CO 2 and the corresponding amount of substance:

m (CO 2) \u003d 84 13.2 / 4.2 \u003d 264 g,
n(CO 2) \u003d 264 (g) / 44 (g / mol) \u003d 6 mol, X = 6.
Similarly m(H 2 O) \u003d 84 5.4 / 4.2 \u003d 108 g,
n (H 2 O) \u003d 108 (g) / 18 (g / mol) \u003d 6 mol, y \u003d 12.
C 6 H 12 - hexene.

Each group will hand over their worksheets. Then comes the conclusion of the lesson.

Homework.Rudzitis G.E., Feldman F.G. Chemistry-10. M .: Education, 1999, chapter IV, § 1, p. 30–38, fig. 10, p. 38. Prepare questions 6, 7 for the seminar from the plan for studying the topic of the lesson, learn the material of the lesson-lecture.

Independent work

on this topic:

I option

1. For saturated hydrocarbons, reactions are characteristic:

a) combustion, b) substitution, c) addition. d) neutralization?

2. Given a chain of transformations

1 2 3

C 2 H 6 → C 2 H 5 Cl→ C 4 H 10 → CO 2:

the second reaction is called a) Konovalov, b) Wurtz, c) Semenov.

Write equations for all reactions.

3. Which compound is used to produce methane in the laboratory:
a) CH3COOH, b) CH 3 OH, c) CH 3 C1, d) C H 3 SOO N a

Write an equation for this reaction.

4. The mass fractions of carbon and hydrogen in a hydrocarbon are equal, respectively
82.76% and 17.24%. Its hydrogen vapor density is 29. Derive the formula of the substance. Numberhydrogen atoms in a molecule is a) 12; b) 6; c) 10 d) 14.

"Chemical properties and methods for obtaining alkanes"

II option

1. Which of the following chemical properties are characteristic of methane:

a) hydrogenation, b) isomerization, c) combustion, d) catalytic oxidation?

Write the appropriate reaction equations.

2. As a result of the following transformations

Cl 2 hlNa

CH 4 → X 1 → X 2

the final product is formed (X 2 )

a) propane, b) chloroethane, c) ethane, d) chloromethane?

Write the equations for all reactions.

3. Specify which compound is used to obtain ethane (according to the reaction
Wurtz): a) C 2 H 4, b) CH 3 I, c) CH 3 - O - CH 3, d) C 2 H 5 OH?

4. The mass fraction of carbon in alkane is 81.82%., hydrogen 18.18%. Relative
its vapor density in air is 1.518. Determine the formula for an alkane. The number of carbon atoms in an alkane molecule is a) 4; b) 2; at 6; d) 3.

Give two homologues and two isomers for this hydrocarbon and give them names.

Independent work on the topic:

"Chemical properties and methods for obtaining alkanes"

III option

1. Which of the following reactions are typical for butane:

a) addition, b) cracking, c) isomerization, d) dehydrogenation.

Write equations for these reactions.

2. By what reaction can methane be obtained in the laboratory:
a) CH 3 OH + H 2 → b) CH 3 Br + N a →

c) CaC 2 + H 2 0 → g ) A1 4 C 3 + H 2 0 →

Write an equation for the corresponding reaction.

3. Indicate the conditions that are necessary to start the reaction between ethane and chlorine: a) cooling, b) heating, c) pressure increase, d) lighting. Write an equation for the corresponding reaction

4. The mass fractions of carbon and hydrogen in the hydrocarbon are 81.8% and 18.2%, respectively. Its hydrogen vapor density is 22.

The number of hydrogen atoms in a substance molecule is a) 8; b) 6; at 3; d) 12.

Give two homologues and two isomers for this hydrocarbon and give them names.

Independent work