VPR in chemistry for grade 11 consists of fifteen tasks. 11 of them belong to the basic level of complexity, and only 4 - to the advanced one. Tasks are divided into 4 blocks:

In order to write a paper, students are given 90 minutes, that is, 2 lessons. During the VPR in chemistry, eleventh graders are allowed to carry the following things with them:

1. Calculator (non-programmable)
2. Periodic table of D. I. Mendeleev
3. Electrochemical series of voltages of metals
4. Solubility table

Grading system

In total, you can score 33 points for the work. There is no clearly defined scale for their translation into grades - this is done at the discretion of the management of the educational institution.

Examples of tasks with scores and explanations

Exercise 1

The first task opens a block of numbers that test students' knowledge in the field of theoretical foundations of chemistry. At the beginning, the topic of the task is set - for example, methods for separating mixtures or methods for collecting gas (they are listed). There are 3 drawings (without captions) illustrating what in question in the text, for example, three ways of separating mixtures. Next, you need to correlate the number of the figure with the provisions of the table indicated in the assignment, and also indicate what this figure illustrates (for example, a method or method). The table might look like this:

If the entire table is filled in correctly, the student receives 2 points for this task. If there is an error in one of its elements - 1 point, and if there are 2 or more errors - 0 points.

Task 2

In the second task, the knowledge of eleventh graders is tested in such aspects of chemistry as the composition of the atom and its structure. electron shell. The condition contains a picture that shows a model of the structure or a diagram of the distribution of electrons over the levels of an element - for example, like this:

It is necessary to answer three questions: write the serial number of the element, the number of the period and the group in which it is located, and also determine whether the simple substance formed by the element belongs to metals or non-metals.

If the whole answer is correct - 2 points are given, with one mistake - 1 point, with two or more - 0.

Task 3

This issue involves working with the periodic system of D. I. Mendeleev, knowledge of its laws and properties of elements. A list of 4 elements is given - for example, Si, O, N, P or Si, Al, S, Cl. It is necessary to arrange them according to the condition - for these examples, this is a decrease in the radii of atoms and an increase in acidic properties higher oxides- and write in the answer in the correct order. For a correct answer, the student receives 1 point, for an incorrect one - 0.

Task 4

The fourth task of the VLOOKUP in chemistry is related to the structure of chemicals and their properties. A table is given in which the main properties of substances of molecular and ionic structure are displayed. Next, you need to determine what structure the two given substances have - for example, iodine and carbon monoxide or baking soda and acetylene. If the structure of both substances is determined correctly, the eleventh grader receives 2 points for this task, if only one - 1 point, and if the entire answer is incorrect - 0 points.

Task 5

The fifth task opens a block of numbers related to inorganic chemistry. It is connected with the classification of inorganic compounds. A table is provided; in its first two columns, the formulas of substances are written, but the classes to which they belong are omitted, and in the next two, vice versa. It might look like this:

You need to complete the table with the missing elements. If this is done correctly - the answer is estimated at 2 points, if one mistake is made - 1 point, if two or more - 0 points.

Further in the text of the work is a text about any chemical substance– e.g. aluminum sulfate or ammonia. The text says how to get it, appearance, use in life and industry, basic properties and reactions. Tasks 6-8, which include two questions each, are performed based on this text. For each of tasks 6, 7 and 8, you can get a maximum of 2 points - if the answer is completely correct. If there is 1 mistake, 1 point is given, and if the answer is incorrect - 0 points.

Tasks 6-8

All these tasks are built according to the same principle - in the first part, you need to draw up an equation for any reaction involving the substance (or derivatives from it) that is mentioned in the text. All components of the reaction are indicated, and other details of the answer are also mentioned - for example, that the equation should be abbreviated, or that it should reflect the reaction that occurs before the formation of a precipitate.

For example, if the text is about aluminum sulfate, the first parts of the questions look like this:

• Write a molecular equation for the reaction of obtaining aluminum sulfate from aluminum oxide and sulfuric acid.
• Write a molecular equation for the reaction between aluminum sulfate and sodium hydroxide, proceeding until a precipitate forms.
• Make an abbreviated ionic equation reactions between aluminum hydroxide and sulfuric acid.

In the second part, questions are asked related to the written equation - about the type of reaction, about its signs, about the properties of the resulting substance. For our example, they look like this:

• Describe the signs of an ongoing reaction.
• Explain why the resulting precipitate dissolves in excess alkali.
• What type of reactions (compound, decomposition, substitution, exchange) does this interaction belong to?

Task 9

The ninth number of the VLOOKUP in chemistry, relating to elevated level complexity, checks the ability of students to work with redox reactions - to compile their electronic balances, set the coefficients and indicate which substance is an oxidizing agent and which acts as a reducing agent. The reaction scheme is given - for example:

Fe(OH)2 + NaBrO + H2O → Fe(OH)3 + NaBr

CH4 + NO2 → CO2 + NO + H2O

The task consists of 3 parts. First, you need to make electronic balance, in the second - indicate the reducing agent / oxidizing agent, and in the third - arrange the coefficients. If all this is done correctly, the answer is worth 3 points, if the student made a mistake in one part of the answer - 2 points, in two parts - 1 point, and if the entire answer is incorrect - 0 points.

Task 10

The tenth task is somewhat easier than the previous one, although it is also a task of increased difficulty. It gives a chemical chain, usually including three equations - for example:

K2CO3 → CaCO3 → CO2 → NaHCO3

Na2O → NaOH → Na2CO3 → Na2SO4

It is required to write reaction equations. If all three of them are correct, the eleventh grader gets 3 points, if only two are correct, 2 points, if only one is correct, 1 point, and if everything is wrong, 0.

Task 11

The eleventh task opens a block of tasks in organic chemistry. It is necessary to establish a correspondence between the formula of the substance and its name, or between the name of the substance and the class / group to which it belongs. Three names or three formulas are given, indicated by letters, but there are four positions that need to be matched, so it will be more difficult to just pick up the answer. The answer is recorded in the table; if there are no errors, 2 points are given, if one error is 1 point, if two or three are 0 points.

Task 12

In the condition of this task, two reaction schemes are given, in which one substance is omitted. It is necessary to insert the missing substances, and, if necessary, arrange the coefficients. Task examples:

HBr → CH3–CH2–Br + H2O

CH3CH2OH + HCl → ...... + H2O

If the missing elements are written correctly, the answer is estimated at 2 points, with one mistake - 1 point. For an incorrect answer or its absence, the student does not receive points for this task.

Task 13

The thirteenth task is a task, and not the easiest one - it belongs to an increased level of complexity. Most often, it is required to calculate the mass of a substance, sometimes a practical and theoretical yield and deficiency / excess is given. You need to write the equation described in the reaction condition and a detailed solution. Here are some examples of conditions:

• Calculate how many grams of ethyl acetate can be obtained from 600 g acetic acid at 100% practical yield.
• Calculate the mass of calcium chloride, which is formed by the interaction of an excess of hydrochloric acid solution with calcium hydroxide weighing 370 g.

If everything is done correctly - 3 points are given, if there is one mistake - 2 points, two mistakes - 1 point, three or more - 0 points.

Task 14

In the penultimate task of the VLOOKUP in chemistry, the complexity of which is also considered to be increased, it is necessary to compose 3 equations for reactions with organic matter. Unlike task number 10, here is not the result of the reactions, but both of their components.

The condition looks like this:

If all three equations are correct, the answer is 3 points, if only two are correct, 2 points, only one -1 point, none - 0.

Task 15

The fifteenth task involves solving the problem. Most often, it is required to calculate the mass or mass fraction. This problem is easier than the one to be solved in number 13. Examples:

• To prepare the marinade in the cookbook, it is recommended to dissolve 20 g of salt, 30 g of sugar and 10 g of acetic acid in 500 ml of water. Calculate the mass fraction of salt and acetic acid in the resulting marinade.
• To increase the yield, green onions are recommended to be sprayed weekly with a 0.2% solution of ammonium nitrate. Calculate the mass of ammonium nitrate and the mass of water required to prepare 500 g of such a solution.

This task belongs to the block "chemistry and life", therefore, the condition of the task describes practical use received substances. For a correct answer, the student receives 2 points, if there is one mistake in the answer -1 point, in other cases, points for the task are not awarded.

VERIFICATION WORK IN CHEMISTRY

Grade 11

Work instructions

The test work includes 15 tasks. To complete the work in chemistry, 1 hour 30 minutes (90 minutes) is allotted.

Prepare answers in the text of the work according to the instructions for the tasks. If you write down an incorrect answer, cross it out and write down a new one next to it.

When performing work, you are allowed to use the following Additional materials:

– Periodic system chemical elements DI. Mendeleev;

– table of solubility of salts, acids and bases in water;

– electrochemical series of voltages of metals;

– non-programmable calculator.

When completing assignments, you can use a draft. Draft entries will not be reviewed or graded.

We advise you to complete the tasks in the order in which they are given. To save time, skip the task that you can't complete right away and move on to the next one. If after completing all the work you have time left, you can return to the missed tasks.

The points you get for completed tasks are summed up. Try to complete as many tasks as possible and score the most points.

A dispersed system is a system in which one substance in the form of small particles is distributed in the volume of another.

The dispersed phase is a substance that is present in the dispersion system in a smaller amount. It can also consist of several substances.

The dispersion medium is a substance that is present in the dispersion system in a larger amount, and in the volume of which the dispersed phase is distributed.

Fill in the table aggregate states of the dispersion medium and phase

The figure shows the model electronic structure an atom of some chemical element.

Based on the analysis of the proposed model, perform the following tasks:

1) determine the chemical element whose atom has such an electronic structure;

2) indicate the number of protons that this element contains;

3) indicate the number of filled energy levels;

4) determine the maximum valence of this element

Record your answers in a table.

With an increase in the charge of the nucleus of atoms, a gradual regular change in the properties of elements and their compounds from metallic to typically non-metallic is observed, which is associated with an increase in the number of electrons at the external energy level.

Given these patterns, arrange in order of increasing non-metallic properties, the following elements: Na, Cl, Al, Si. Write down the designations of the elements in the desired sequences.

Answer: ____________________________

A hydrogen atom connected to a fluorine, oxygen, or nitrogen atom (less commonly, chlorine, sulfur, or other non-metals) can form one more additional bond. A hydrogen bond is due to the electrostatic attraction of a hydrogen atom (carrying a positive charge δ+) to an atom of an electronegative element having a negative charge δ−. In most cases, it is weaker than covalent, but much stronger than the usual attraction of molecules to each other in solid and liquid substances.

From the proposed compounds, select 2 compounds whose molecules form hydrogen bonds: ethanal, ethanol, hydrogen, ammonia, oxygen.

Write your answer in the space provided:

_________________________

_________________________

Salt-forming oxides are classified into three groups, as shown in the diagram. In this scheme, enter the missing group names and give two examples of chemical formulas of substances belonging to this group.

Read the following text and do tasks 6-8.

Barium sulfate is often used in x-ray studies of the gastrointestinal tract as a radiocontrast agent, since barium's heavy atoms absorb x-rays well. Although all soluble barium salts are poisonous, barium sulfate is practically insoluble in water (and in hydrochloric acid, which is found in gastric juice), so it is non-toxic. For an X-ray examination of the digestive organs, the patient ingests a suspension of barium sulfate (“barite porridge”) with a barium content of 58.7%.

Barium sulfate is obtained by reacting soluble salts, barium oxide, peroxide or hydroxide with sulfuric acid or soluble sulfates. In analytical chemistry, barium sulfate is used as a good gravimetric form for the determination of sulfate ions and barium ions in gravimetric analysis.

In addition, barium sulfate is used as a color component for pyrotechnics, since barium ions contribute to the coloring of the flame in green. Currently, barium nitrate is mainly used for these purposes, due to the fact that it is a strong oxidizing agent and contributes to the vigorous combustion of the pyrotechnic mixture.

1) Write the molecular equation for the reaction for obtaining barium sulfate from barium peroxide, which was mentioned in the text.

Answer: _____________________________________________________

Explain why barium sulfate does not have a toxic effect on the body.

Answer: ________________________________________________________________ ________________________________________________________________________

1) Write a molecular equation for the reaction between barium chloride and sodium sulfate.

Answer: ________

Explain what features of this reaction make it possible to use barium chloride in analytical chemistry.

Answer:

______________________________________________________________________

1) Write an abbreviated ionic equation for the reaction between barium chloride and sodium sulfate.

Answer: _____________________________________________________________

2) Explain why barium nitrate is preferred over barium sulfate as a color component for fireworks.

__________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

The scheme of the redox reaction is given

PH 3 + KMnO 4 + H 2 SO 4 →MnSO 4 + H 3 PO 4 + K 2 SO 4 + H 2 O

Write an electronic balance for this reaction.

______________________________________________________________________

Specify the oxidizing agent and reducing agent

______________________________________________________________________________________________________________________________________________

Arrange the coefficients in the reaction equation

______________________________________________________________________

The transformation scheme is given:Al → Na[ Al( Oh) 4 ] → AlCl 3 → Al( Oh) 3

Write the molecular equations of the reactions by which these transformations can be carried out.

________________________________________________________________

________________________________________________________________

_________________________________________________________________

Match the title organic matter and the class/group to which the substance belongs: for each position indicated by a letter, select the corresponding position indicated by a number.

SUBSTANCE NAME CLASS/GROUP

A) Toluene 1) alcohols

B) Acetylene 2) alkenes

C) Ethanol 3) arenas

4) alkynes

Write in the table the selected numbers under the corresponding letters.

Answer:

In the proposed schemes chemical reactions insert the formulas of the missing substances and arrange the coefficients

CaC 2 + H 2 O→ …….. + ……………….

CH 3 NH 2 + ……….. → ……….. + N 2 + H 2 O

The raw materials for the production of sulfuric acid are native sulfur and sulfide ores. Among them highest value has iron pyrite - pyrite FeS 2 . In nature, it occurs in massive dense layers, from which it is extracted in the form of pieces that are crushed and crushed. In the production of sulfuric acid from pyrite, sulfur dioxide is obtained by roasting iron pyrites.

What mass of pyrite is needed to produce 67.2 liters of sulfur dioxide (n.o.s.)? Write down a detailed solution to the problem.

________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

Acetone is a popular solvent used as a raw material for the synthesis of many important chemical products, such as acetic anhydride, methyl methacrylate. Acetone is a natural metabolite produced by mammalian organisms, including human body. In accordance with the scheme below, write the equations for the reactions for obtaining acetone. When writing reaction equations, use the structural formulas of organic substances.

_________________________________________________________

_________________________________________________________

_________________________________________________________

Glauber's salt Na 2 SO 4 .10H 2 O is used in the treatment of gastrointestinal diseases as a laxative. How much (g) Na 2 SO 4 .10H 2 O is needed to prepare 250 g of a solution, with a mass fraction of Na 2 SO 4 equal to 5%. Write down a detailed solution to the problem.

Answers

Na, Al, Si, Cl

1. 1) ethanol 2) ammonia

2. Points

   Response elements:

   Group names recorded: basic, amphoteric

   The formulas of the substances of the corresponding groups are written

   Group names are correct

   Two or more errors were made
Correct Answer Content and Grading Instructions

(Other formulations of the answer are allowed that do not distort its meaning)

Points

Response elements:

BaO 2 + H 2 SO 4 = BaSO 4 + H 2 O 2

Barium sulfate, due to its low solubility in water, is not a toxic substance for the body, unlike all soluble barium salts, and therefore it can be used as a radiopaque substance.

The answer is correct and complete, contains all the above elements

1. Correct Answer Content and Grading Instructions

   (Other formulations of the answer are allowed that do not distort its meaning)

   Points

   Response elements:

   BaCl 2 + Na 2 SO 4 = BaSO 4 + 2NaCl

   As a result of this reaction, an insoluble substance is formed - barium sulfate, a precipitate white color(qualitative reaction to sulfate ions and barium ions)

   The answer is correct and complete, contains all the above elements

   The response includes one of the above elements

   All elements of the answer are written incorrectly

2. Correct Answer Content and Grading Instructions

   (Other formulations of the answer are allowed that do not distort its meaning)

   Points

   Response elements:

   Ba 2+ + SO 4 2- = BaSO 4

   Barium nitrate is a strong oxidizing agent and promotes vigorous combustion of the pyrotechnic mixture.

   The answer is correct and complete, contains all the above elements

   The response includes one of the above elements

   All elements of the answer are written incorrectly

3. Correct Answer Content and Grading Instructions

   (Other formulations of the answer are allowed that do not distort its meaning)

   Points

   Response elements:

   Compiled electronic balance:

   P -3 -8 ē →P +5 5

   Mn +7 + 5 ē →Mn +2 8

   It is stated thatPH 3 at the expenseP -3 is a restorer

   aKMnO 4 at the expenseMn +7 is an oxidizing agent;

   3) The reaction equation is composed:

   5 PH 3 + 8 KMnO 4 +12 H 2 SO 4 →8 MnSO 4 +5 H 3 PO 4 +4 K 2 SO 4 + 12 H 2 O

   The answer is correct and complete, contains all the above elements

   All elements of the answer are written incorrectly

4. Correct Answer Content and Grading Instructions

   (Other formulations of the answer are allowed that do not distort its meaning)

   Points

   The reaction equations corresponding to the transformation scheme are written:

   Al → Na → AlCl 3 →Al(OH) 3

   2Al + 2NaOH + 6H 2 O → 2Na + 3H 2

   Na + 4HCl (excess) → NaCl + AlCl 3 + 4H 2 O

   AlCl 3 + 3 KOH → Al(OH) 3 + 3 KCl
Correct Answer Content and Grading Instructions

(Other formulations of the answer are allowed that do not distort its meaning)

Points

Response elements:

CaC 2 + H 2 O → Ca(OH) 2 + HC≡CH

CH 3 NH 2 + HNO 2 → CH 3 OH+N 2 + H 2 O

4CH 3 NH 2 + 9O 2 →4 CO 2 + 2N 2 +10H 2 O

The answer is correct and complete, contains all the above elements

2

An error was made in one of the response elements

1

All elements of the answer are written incorrectly

0

13. Correct Answer Content and Grading Instructions

    (Other formulations of the answer are allowed that do not distort its meaning)

    Points

    Response elements:

    An equation for the reaction of pyrite roasting is compiled

    4 FeS 2 + 11O 2 = 2Fe 2 O 3 + 8SO 2

    n(SO 2 ) = V(SO 2 )/ V m = 67,2 l/ 22,4 l/ mole = 3 mole

    n(FeS 2 ) = n(SO 2 )/2 = 3 mole/2 = 1,5 mole

    m(FeS 2 ) = n* M\u003d 1.5 mol * 120 g / mol \u003d 180 g.

    The answer is correct and complete, contains all the above elements

    3

    Correctly written two of the above elements of the answer

    2

    One of the above elements of the answer is correctly written

    1

    All elements of the answer are written incorrectly Three reaction equations are written correctly

    3

    Correctly written two reaction equations

    2

    Correctly written one reaction equation

    1

    All equations are written incorrectly or there is no answer

    0

    15

    Correct Answer Content and Grading Instructions

    (Other formulations of the answer are allowed that do not distort its meaning)

    Points

    Response elements:

    m(Na 2 SO 4 = =

    250 . 0,05 = 12,5 G;

    2) Na 2 SO 4 Na 2 SO 4 . 10H 2 O

    ( Na 2 SO 4 ) =  ( Na 2 SO 4 . 10H 2 O)

    m(Na 2 SO 4 . 10H 2 O) = 12.5 . 322/142 = 28.4 g

    Answer: 28.4 g.

    The answer is correct and complete, contains all the above elements

    2

    The response includes one of the above elements

    1

    All elements of the answer are written incorrectly

    0

In 2018, VPR in chemistry in 11 classes was carried out by decision educational organization, for graduates who did not choose this subject for passing the exam.

The 2018 versions will come in handy to prepare for the 2019 CDF.

VPR in chemistry grade 11 2018 options + answers

The verification work in chemistry is conditionally divided into four substantive blocks: "Theoretical Foundations of Chemistry", " Inorganic chemistry”, “Organic chemistry”, “Methods of knowledge of chemistry. Experimental foundations of chemistry. Chemistry and Life.

Graduates taking part in the writing of a chemistry CDF must demonstrate a basic level of subject knowledge:

• write an equation for a chemical reaction
• simulate a chemical experiment based on its description,
• explain the conditionality of the properties and methods of obtaining substances by their composition and structure.

Test work for grade 11 includes 15 tasks various levels difficulties.

1.5 hours (90 minutes) are given to complete the entire work.

The tasks included in the test work check mastery
graduates with certain skills and methods of action that
meet the requirements for the level of training of graduates.

Table for converting the scores of the VLOOKUP of chemistry to the assessment

VPR All-Russian Testing Work- Chemistry Grade 11

Explanations to the model of the All-Russian verification work

When familiarizing yourself with the sample test work, it should be borne in mind that the tasks included in the sample do not reflect all the skills and content issues that will be tested as part of the All-Russian test work. A complete list of content elements and skills that can be tested in the work is given in the codifier of content elements and requirements for the level of training of graduates for the development of the All-Russian test work in chemistry. The purpose of the test work sample is to give an idea of ​​the structure of the All-Russian test work, the number and form of tasks, and their level of complexity.

Work instructions

The test work includes 15 tasks. To complete the work in chemistry, 1 hour 30 minutes (90 minutes) is allotted.
Prepare answers in the text of the work according to the instructions for the tasks. If you write down an incorrect answer, cross it out and write down a new one next to it.
When performing work, it is allowed to use the following additional materials:
– Periodic system of chemical elements D.I. Mendeleev;
- table of solubility of salts, acids and bases in water;
– electrochemical series of voltages of metals;
- non-programmable calculator.
When completing assignments, you can use a draft. Draft entries will not be reviewed or graded.
We advise you to complete the tasks in the order in which they are given. To save time, skip the task that you can't complete right away and move on to the next one. If after completing all the work you have time left, you can return to the missed tasks.
The points you get for completed tasks are summed up. Try to complete as many tasks as possible and score the most points.
We wish you success!

1. From the course of chemistry, you know the following methods for separating mixtures: sedimentation, filtration, distillation (distillation), magnet action, evaporation, crystallization. Figures 1-3 show examples of some of these methods.

Which of the following methods of separation of mixtures can be used for purification:
1) flour from iron filings that got into it;
2) water from inorganic salts dissolved in it?
Record in the table the number of the figure and the name of the corresponding method for separating the mixture.

iron filings are attracted by a magnet

during distillation, after the condensation of water vapor, salt crystals remain in the vessel

2. The figure shows a model of the electronic structure of an atom of some chemicalelement.

Based on the analysis of the proposed model, perform the following tasks:
1) determine the chemical element whose atom has such an electronic structure;
2) indicate the period number and group number in the Periodic system of chemical elements D.I. Mendeleev, in which this element is located;
3) determine whether a simple substance that forms this chemical element belongs to metals or non-metals.
Record your answers in a table.
Answer:

N; 2; 5 (or V); non-metal

to determine the chemical element, you should calculate the total number of electrons, which we see in figure (7)

taking the periodic table, we can easily determine the element (the number of electrons found is equal to the atomic number of the element) (N-nitrogen)

after that, we determine the group number (vertical column) (5) and the nature of this element (non-metal)

3. Periodic system of chemical elements D.I. Mendeleev- a rich repository of information about chemical elements, their properties and properties of their compounds, about the patterns of changes in these properties, about methods for obtaining substances, as well as about their presence in nature. So, for example, it is known that with an increase in the ordinal number of a chemical element in periods, the radii of atoms decrease, and in groups they increase.
Given these patterns, arrange the following elements in order of increasing atomic radii: N, C, Al, Si. Write down the designations of the elements in the correct sequence.

Answer: ____________________________

N → C → Si → Al

4. The table below lists characteristic properties substances that have a molecular and ionic structure.

Using this information, determine what structure the substances nitrogen N2 and table salt NaCl have. Write your answer in the space provided:

1) nitrogen N2 ________________________________________________________________
2) table salt NaCl _________________________________________________

nitrogen N2 - molecular structure;
table salt NaCl - ionic structure

5. Complex inorganic substances conditionally, it can be distributed, that is, classified, into four groups, as shown in the diagram. In this chart, for each of the four groups, fill in the missing group names or chemical formulas substances (on one example of formulas) belonging to this group.

The names of the groups are recorded: bases, salts;
the formulas of the substances of the corresponding groups are written down

CaO, bases, HCl, salts

Read the following text and do tasks 6-8.

In the food industry, the food additive E526 is used, which is calcium hydroxide Ca (OH) 2. It finds application in the production of: fruit juices, baby food, pickles, table salt, confectionery and sweets.
Production of calcium hydroxide on an industrial scale is possible by mixing calcium oxide with water, this process is called quenching.
Calcium hydroxide has been widely used in the production of such building materials like whitewash, plaster and gypsum mortars. This is due to his ability interact with carbon dioxide CO2 contained in the air. The same property of calcium hydroxide solution is used to measure the quantitative content carbon dioxide in the air.
A useful property of calcium hydroxide is its ability to act as a flocculant that purifies wastewater from suspended and colloidal particles (including iron salts). It is also used to raise the pH of water, since natural water contains substances (for example, acids), causing corrosion in plumbing pipes.

1. Write a molecular equation for the reaction to produce calcium hydroxide, which
mentioned in the text.

2. Explain why this process is called quenching.
Answer:__________________________________________________________________________

________________________________________________________________________________

1) CaO + H 2 O \u003d Ca (OH) 2
2) When calcium oxide interacts with water, a large amount of
the amount of heat, so the water boils and hisses, as if it hits hot coal, when the fire is extinguished with water (or “extinguishing this process is called because slaked lime is formed as a result”)

1. Write a molecular equation for the reaction between calcium hydroxide and carbon dioxide
gas, which was mentioned in the text.
Answer:__________________________________________________________________________

2. Explain what features of this reaction make it possible to use it to detect
carbon dioxide in the air.
Answer:__________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________

1) Ca(OH) 2 + CO 2 = CaCO 3 ↓ + H 2 O
2) As a result of this reaction, an insoluble substance is formed - calcium carbonate, clouding of the initial solution is observed, which makes it possible to judge the presence of carbon dioxide in the air (qualitative
reaction to CO 2)

1. Make an abbreviated ionic equation of the reaction mentioned in the text between
calcium hydroxide and hydrochloric acid.
Answer:__________________________________________________________________________

2. Explain why this reaction is used to increase the pH of water.
Answer:__________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________

1) OH - + H + = H 2 O (Ca(OH) 2+ 2HCl = CaCl2 + 2H2O)
2) The presence of acid in natural water causes low pH values ​​of this water. Calcium hydroxide neutralizes the acid and pH values ​​rise

The pH scale exists from 0-14. from 0-6 - acidic environment, 7 - neutral environment, 8-14 - alkaline environment

9. The scheme of the redox reaction is given.

H 2 S + Fe 2 O 3 → FeS + S + H 2 O

1. Make an electronic balance of this reaction.
Answer:__________________________________________________________________________

2. Specify the oxidizing agent and reducing agent.
Answer:__________________________________________________________________________

3. Arrange the coefficients in the reaction equation.
Answer:__________________________________________________________________________

1) Compiled electronic balance:

2Fe +3 + 2ē → 2Fe +2	2		1
		2
S -2 - 2ē → S 0	2		1

2) It is indicated that sulfur in the oxidation state –2 (or H 2 S) is a reducing agent, and iron in the oxidation state +3 (or Fe 2 O 3) is an oxidizing agent;
3) The reaction equation is composed:
3H 2 S + Fe 2 O 3 \u003d 2FeS + S + 3H 2 O

10. The scheme of transformations is given:

Fe → FeCl 2 → Fe(NO 3) 2 → Fe(OH) 2

Write the molecular reaction equations that can be used to carry out
indicated transformations.
1) _________________________________________________________________________
2) _________________________________________________________________________
3) _________________________________________________________________________

The reaction equations corresponding to the transformation scheme are written:
1) Fe + 2HCl = FeCl 2 + H 2
2) FeCl 2 + 2AgNO 3 \u003d Fe (NO 3) 2 + 2AgCl
3) Fe(NO 3) 2 + 2KOH = Fe(OH) 2 + 2KNO 3
(Other ones that do not contradict the condition of setting the equation are allowed
reactions.)

11. Establish a correspondence between the formula of organic matter and the class / group to which this substance belongs: for each position indicated by a letter, select the corresponding position indicated by a number.

Write in the table the selected numbers under the corresponding letters.
Answer:

A	B	V

1. C3H8 - CnH2n + 2 - alkane
2. C3H6 - CnH2n- alkene
3. C2H6O - CnH2n + 2O- alcohol

12. In the proposed schemes of chemical reactions, insert the formulas of the missing substances and arrange the coefficients.

1) C 2 H 6 + ……………..… → C 2 H 5 Cl + HCl
2) C 3 H 6 + ……………..… → CO 2 + H 2 O

1) C 2 H 6 + Cl 2 → C 2 H 5 Cl + HCl
2) 2C 3 H 6 + 9O 2 → 6CO 2 + 6H 2 O
(Fractional odds are possible.)

13. Propane burns with low level release of toxic substances into the atmosphere, therefore it is used as an energy source in many areas, for example, in gas lighters and for heating country houses.
What volume of carbon dioxide (N.O.) is formed during the complete combustion of 4.4 g of propane?
Write down a detailed solution to the problem.
Answer:__________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________

1) An equation for the reaction of propane combustion was compiled:
C 3 H 8 + 5O 2 → 3CO 2 + 4H 2 O
2) n (C 3 H 8) \u003d 4.4 / 44 \u003d 0.1 mol
n (CO 2) \u003d 3n (C 3 H 8) \u003d 0.3 mol
3) V (O 2) \u003d 0.3 22.4 \u003d 6.72 l

14. Isopropyl alcohol is used as a universal solvent: it is part of the products household chemicals, perfumery and cosmetic products, windshield washer fluids for cars. In accordance with the scheme below, make up the equations for the reactions for obtaining this alcohol. When writing reaction equations, use the structural formulas of organic substances.

1) _______________________________________________________
2) _______________________________________________________
3) _______________________________________________________

The reaction equations are written corresponding to the scheme:

(Other ones are allowed that do not contradict the condition of setting the reaction equation.)

15. Physiological saline in medicine is called a 0.9% solution of sodium chloride in water. Calculate the mass of sodium chloride and the mass of water required to prepare 500 g of saline. Write down a detailed solution to the problem.
Answer:__________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________

1) m(NaCl) = 4.5 g
2) m(water) = 495.5 g

m(r-ra) = 500g m(salt) = x

x/500 * 100%= 0.9%

m(salts) = 500* (0.9/100)= 4.5 g

© 2017 Federal Service for Supervision in Education and Science Russian Federation

VLOOKUP. Chemistry. Grade 11. 10 options for typical tasks. Drozdov A.A.

M.: 20 1 7. - 9 6 p.

This manual is fully consistent with the federal state educational standard(second generation). The book contains 10 variants of typical tasks of the All-Russian Testing Work (VPR) in chemistry for 11th grade students. The collection is intended for 11th grade students, teachers and methodologists using typical tasks to prepare for the All-Russian test work in chemistry.

Format: pdf

The size: 3.4 MB

Watch, download:drive.google

Work instructions, 4
Option 1 5
Option 2 12
Option 3 19
Option 4 26
Option 5 33
Option 6 40
Option 7 47
Option 8 54
Option 9 61
Option 10 68
Assessment system for test work 75
Answers 76
Applications 93

The test work includes 15 tasks. To complete the work in chemistry, 1 hour 30 minutes (90 minutes) is allotted.
Prepare answers in the text of the work according to the instructions for the tasks. If you write down an incorrect answer, cross it out and write down a new one next to it.
When performing work, it is allowed to use the following additional materials:
- Periodic system of chemical elements D.I. Mendeleev;
- table of solubility of salts, acids and bases in water;
- electrochemical series of voltages of metals;
- non-programmable calculator.
When completing assignments, you can use a draft. Draft entries will not be reviewed or graded.
We advise you to complete the tasks in the order in which they are given. To save time, skip the task that you can't complete right away and move on to the next one. If after completing all the work you have time left, you can return to the missed tasks.
The points you get for completed tasks are summed up. Try to complete as many tasks as possible and score the most points.