Sodium nitride weighing 8.3 g reacted with sulfuric acid with a mass fraction of 20% and a mass of 490 g. Then crystalline soda weighing 57.2 g was added to the resulting solution. Find the mass fraction (%) of the acid in the final solution. Write down the reaction equations that are indicated in the condition of the problem, give all the necessary calculations (indicate the units of measurement of the desired physical quantities). Round your answer to the nearest whole number.

Real USE 2017. Task 34.

The cyclic substance A (does not contain oxygen and substituents) is oxidized with a ring break to substance B weighing 20.8 g, the combustion products of which are carbon dioxide with a volume of 13.44 liters and water with a mass of 7.2 g. Based on the given conditions of the assignment: 1) perform the calculations necessary to establish the molecular formula organic matter B; 2) write down molecular formulas organic substances A and B; 3) compose structural formulas organic substances A and B, which unambiguously reflect the order of bonding of atoms in a molecule; 4) write the equation for the reaction of oxidation of substance A with potassium permanganate sulfate solution to form substance B. In the answer for the site, indicate the sum of all atoms in one molecule of the original organic substance A.

USE 2017 Chemistry Typical test tasks Medvedev

M.: 2017. - 120 p.

Typical test tasks in chemistry contain 10 options for sets of tasks, compiled taking into account all the features and requirements of the Unified State Exam in 2017. The purpose of the manual is to provide readers with information about the structure and content of KIM 2017 in chemistry, the degree of difficulty of tasks. The collection contains answers to all test options and provides solutions to all tasks of one of the options. In addition, examples of forms used in the exam are given to record answers and decisions. The author of the tasks is a leading scientist, teacher and methodologist, who is directly involved in the development of control measuring instruments. USE materials. The manual is intended for teachers to prepare students for the exam in chemistry, as well as for high school students and graduates - for self-training and self-control.

Format: pdf

Size: 1.5 MB

Watch, download:drive.google

CONTENT
Preface 4
Work instructions 5
OPTION 1 8
Part 1 8
Part 2, 15
OPTION 2 17
Part 1 17
Part 2 24
OPTION 3 26
Part 1 26
Part 2 33
OPTION 4 35
Part 1 35
Part 2 41
OPTION 5 43
Part 1 43
Part 2 49
OPTION 6 51
Part 1 51
Part 2 57
OPTION 7 59
Part 1 59
Part 2 65
OPTION 8 67
Part 1 67
Part 2 73
OPTION 9 75
Part 1 75
Part 2 81
OPTION 10 83
Part 1 83
Part 2 89
ANSWERS AND SOLUTIONS 91
Answers to the tasks of part 1 91
Solutions and answers to tasks of part 2 93
Solution of tasks of option 10 99
Part 1 99
Part 2 113

The present tutorial is a collection of tasks to prepare for the Unified State Exam (USE) in chemistry, which is like a final exam for the course high school as well as university entrance exams. The structure of the manual reflects modern requirements for the procedure passing the exam in chemistry, which will allow you to better prepare for new forms of final certification and for admission to universities.
The manual consists of 10 options for tasks, which in form and content are close to USE demos and do not go beyond the content of the course of chemistry, normatively determined by the Federal component state standard general education. Chemistry (Order of the Ministry of Education No. 1089 dated March 5, 2004).
Content Presentation Level educational material in tasks it is correlated with the requirements of the state standard for the preparation of graduates of a secondary (complete) school in chemistry.
Three types of tasks are used in the control measuring materials of the Unified State Exam:
- tasks basic level Difficulties with short answers
- tasks advanced level Difficulties with short answers
- tasks high level Difficulties with a detailed answer.
Each option examination work built according to a single plan. The work consists of two parts, including a total of 34 tasks. Part 1 contains 29 short answer items, including 20 basic difficulty items and 9 advanced difficulty items. Part 2 contains 5 tasks of a high level of complexity, with a detailed answer (tasks numbered 30-34).
In tasks of a high level of complexity, the text of the solution is written on a special form. Tasks of this type make up the bulk of the written work in chemistry at the entrance exams to universities.

USE 2017 Chemistry Typical test tasks Medvedev

M.: 2017. - 120 p.

Typical test tasks in chemistry contain 10 options for sets of tasks, compiled taking into account all the features and requirements of the Unified State Exam in 2017. The purpose of the manual is to provide readers with information about the structure and content of KIM 2017 in chemistry, the degree of difficulty of tasks. The collection contains answers to all test options and provides solutions to all tasks of one of the options. In addition, examples of forms used in the exam are given to record answers and decisions. The author of the tasks is a leading scientist, teacher and methodologist, who is directly involved in the development of control measuring materials for the exam. The manual is intended for teachers to prepare students for the exam in chemistry, as well as for high school students and graduates - for self-training and self-control.

Format: pdf

Size: 1.5 MB

Watch, download:drive.google

This textbook is a collection of tasks to prepare for the Unified State Exam (USE) in chemistry, which is both a final exam for a high school course and an entrance exam to a university. The structure of the manual reflects the modern requirements for the procedure for passing the exam in chemistry, which will allow you to better prepare for new forms of final certification and for admission to universities.
The manual consists of 10 options for tasks, which in form and content are close to the demo version of the Unified State Examination and do not go beyond the content of the chemistry course, which is normatively determined by the Federal Component of the State Standard for General Education. Chemistry (Order of the Ministry of Education No. 1089 dated March 5, 2004).
The level of presentation of the content of the educational material in the assignments is correlated with the requirements of the state standard for the preparation of graduates of a secondary (complete) school in chemistry.
Three types of tasks are used in the control measuring materials of the Unified State Exam:
- tasks of the basic level of complexity with a short answer,
- tasks of an increased level of complexity with a short answer,
- tasks of a high level of complexity with a detailed answer.
Each version of the examination paper is built according to a single plan. The work consists of two parts, including a total of 34 tasks. Part 1 contains 29 short answer items, including 20 basic difficulty items and 9 advanced difficulty items. Part 2 contains 5 tasks of a high level of complexity, with a detailed answer (tasks numbered 30-34).
In tasks of a high level of complexity, the text of the solution is written on a special form. Tasks of this type make up the bulk of the written work in chemistry at the entrance exams to universities.

For 2-3 months it is impossible to learn (repeat, pull up) such a complex discipline as chemistry.

There are no changes in KIM USE 2020 in chemistry.

Don't delay your preparation.

Before starting the analysis of tasks, first study theory. The theory on the site is presented for each task in the form of recommendations that you need to know when completing the task. guides in the study of the main topics and determines what knowledge and skills will be required when completing the USE tasks in chemistry. For the successful passing of the exam in chemistry, theory is the most important thing.
Theory needs to be backed up practice constantly solving problems. Since most of the errors are due to the fact that I read the exercise incorrectly, I did not understand what is required in the task. The more often you solve thematic tests, the faster you will understand the structure of the exam. Training tasks developed on the basis of demos from FIPI give them the opportunity to decide and find out the answers. But do not rush to peek. First, decide for yourself and see how many points you have scored.

Points for each task in chemistry

1 point - for 1-6, 11-15, 19-21, 26-28 tasks.
2 points - 7-10, 16-18, 22-25, 30, 31.
3 points - 35.
4 points - 32, 34.
5 points - 33.

Total: 60 points.

The structure of the examination paper consists of two blocks:

Questions that require a short answer (in the form of a number or word) - tasks 1-29.
Tasks with detailed answers - tasks 30-35.

3.5 hours (210 minutes) are allotted to complete the examination paper in chemistry.

There will be three cheat sheets on the exam. And they need to be dealt with.

This is 70% of the information that will help you successfully pass the exam in chemistry. The remaining 30% is the ability to use the provided cheat sheets.

If you want to get more than 90 points, you need to spend a lot of time on chemistry.
To successfully pass the exam in chemistry, you need to decide a lot:, training tasks even if they seem light and of the same type.
Correctly distribute your strength and do not forget about the rest.

Dare, try and you will succeed!

Typical test tasks in chemistry contain 10 options for sets of tasks, compiled taking into account all the features and requirements of the Unified State Exam in 2017. The purpose of the manual is to provide readers with information about the structure and content of KIM 2017 in chemistry, the degree of difficulty of tasks.
The collection contains answers to all test options and provides solutions to all tasks of one of the options. In addition, examples of forms used in the exam are given to record answers and decisions.
The author of the tasks is a leading scientist, teacher and methodologist, who is directly involved in the development of control measuring materials for the exam.
The manual is intended for teachers to prepare students for the exam in chemistry, as well as for high school students and graduates - for self-training and self-control.

Examples.
Ammonium chloride contains chemical bonds:
1) ionic
2) covalent polar
3) covalent non-polar
4) hydrogen
5) metal

From the proposed list of substances, select two substances, with each of which copper reacts.
1) zinc chloride (solution)
2) sodium sulfate (solution)
3) dilute nitric acid
4) concentrated sulfuric acid
5) aluminum oxide

CONTENT
Foreword
Work instructions
OPTION 1
Part 1
Part 2
OPTION 2
Part 1
Part 2
OPTION 3
Part 1
Part 2
OPTION 4
Part 1
Part 2
OPTION 5
Part 1
Part 2
OPTION 6
Part 1
Part 2
OPTION 7
Part 1
Part 2
OPTION 8
Part 1
Part 2
OPTION 9
Part 1
Part 2
OPTION 10
Part 1
Part 2
ANSWERS AND SOLUTIONS
Answers to the tasks of part 1
Solutions and answers to the tasks of part 2
Solution of tasks of option 10
Part 1
Part 2.

Free download e-book in a convenient format, watch and read:
Download the book USE 2017, Chemistry, Typical test tasks, Medvedev Yu.N. - fileskachat.com, fast and free download.

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OGE 2019, Chemistry. 32 options, Typical test tasks from the developers of the OGE, Molchanova G.N., Medvedev Yu.N., Koroshenko A.S., 2019
Chemistry, Unified State Exam, Preparing for the final certification, Kaverina A.A., Medvedev Yu.N., Molchanova G.N., Sviridenkova N.V., Snastina M.G., Stakhanova S.V., 2019

Real USE 2017. Task 34.

USE 2017 Chemistry Typical test tasks Medvedev

USE 2017 Chemistry Typical test tasks Medvedev

Points for each task in chemistry

The structure of the examination paper consists of two blocks:

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