Secondary education and schools

Arsenic is a chemical element of the nitrogen group (group 15 of the periodic table). Exists in both gray and yellow crystalline form. Last modified: 2025-06-01 07:06

The strict ban on division by zero is imposed even in the lower grades of the school. Children usually do not even think about its reasons, but to know why something is forbidden is both interesting and useful. Last modified: 2025-01-23 12:01

The length of the suspension bridge across the Sunda Strait will be about 30 km. If the structure is able to withstand the frequent tsunamis and earthquakes in this region, then it will be an outstanding achievement of engineering and will play an important role in the economic development of all of Asia. Last modified: 2025-01-23 12:01

One of the most dangerous types of natural disasters that a person is not able to prevent, stop or control is a volcanic eruption. It occurs due to constant changes in the composition of the earth's crust, as well as due to the movement of its plates. Last modified: 2025-01-23 12:01

The most contrasting and most colorful on our planet is considered to be the African continent. Photos of the nature of this continent are striking in their beauty and colorfulness. If we consider it from a social point of view, then it will also be the poorest on Earth. In this article we will consider the main features of the nature and population of Africa. Last modified: 2025-01-23 12:01

Writing a story based on what they heard may seem like a really difficult task to some, despite the fact that there is nothing difficult in the process. However, if you do not understand such issues, you should not panic ahead of time, because from the article you will learn how to make the process of writing easier for yourself. Last modified: 2025-01-23 12:01

If you need a miniature essay "View from the window", you've come to the right place. No, you will not find a ready-made text here, but you will understand how easy and correct it is to write such a story, so that both you and your listeners/readers/teachers will like it. Last modified: 2025-01-23 12:01

Writing an essay on the topic "Friends" is much easier than analyzing the work or trying to speak out about something you have no idea about. Last modified: 2025-01-23 12:01

If you need to write an essay about nature, you have come to the right place. The article will discuss in detail how to write correctly, what topics to cover and what exactly should be present in the text. Do everything possible to make your essay about nature the most memorable and spectacular, and we will help you with this. Last modified: 2025-01-23 12:01

Atoms of the same type can be part of different substances. For the element denoted by the symbol "O" (from the Latin name Oxygenium), two simple substances common in nature are known. Last modified: 2025-01-23 12:01

The subject of our review today will be Iceland. Description of the country, interesting facts, sights - all this in the material below. Last modified: 2025-01-23 12:01

Autumn is a fertile time of the year that gives people delicious fruits. In addition to benefiting the body and saturating it with vitamins, they also bring aesthetic pleasure. After all, in the fall there is an opportunity to dream up and show creativity in the manufacture of crafts for the fair to school. Last modified: 2025-01-23 12:01

Fujiyama is a volcano that is considered one of the most beautiful on our planet. It is located in Japan, where it has been deified for centuries. It should be noted that even now in this country the mountain is considered a sacred national symbol. Last modified: 2025-06-01 07:06

The Russian Federation is the largest country on the planet. The area of the largest state is just over 17 million square kilometers. This is approximately 11.5% of the entire earth's surface. The country is located on the continent of Eurasia and is crossed by nine time zones. Last modified: 2025-01-23 12:01

The largest countries by population - where are they located? How many people live in them? You will find answers to these questions in the article. In addition, we will talk here about how they are trying to solve the problem of overpopulation in specific states. Last modified: 2025-01-23 12:01

Brazil is the largest country in South America. The characteristic of the country includes a description of the nature, population, state structure, economy and the main problems of development. Read our article and you will learn a lot of new and interesting things about this distant country. Last modified: 2025-01-23 12:01

Boundless expanses of water at all times attracted and frightened people at the same time. Brave sailors set out to travel in search of the unknown. Many mysteries of the oceans remain unsolved today. Last modified: 2025-01-23 12:01

This material describes the cumulation of insurance risks. What does cumulation depend on? What is the cumulation period? Answers to these questions in this article. Last modified: 2025-01-23 12:01

Linguists distinguish such a thing as syllables. Language learners need to be able to correctly determine their boundaries in words and distinguish them by type. Consider the most basic types of syllables, as well as the rules for division. Last modified: 2025-01-23 12:01

The Mexican flag may remind someone of the symbol of Italy. But in fact, these panels have a completely different story. Last modified: 2025-01-23 12:01

Laziness has always been ridiculed and condemned by the people. There are many proverbs about laziness and work that are relevant in our time. Last modified: 2025-01-23 12:01

In any modern system of general education, mathematics occupies one of the central places, which undoubtedly indicates the uniqueness of this field of knowledge. What is modern mathematics? Why is she needed? These and similar questions are often asked to teachers by children. And each time the answer will be different depending on the level of development of the child and his educational needs. Last modified: 2025-01-23 12:01

When asked where the Ore Mountains are located, there are several answers. The most famous mountain range of the same name on the border of Bohemia (Czech Republic) and Saxony (Germany). This region has been known since ancient times as a center for the extraction of copper, silver, tin, and iron. It is one of the origins of metallurgy in Europe. Slovakia has its own Ore Mountains, representing a part of the Western Carpathians. This name is also found in the toponymy of other countries. Last modified: 2025-01-23 12:01

Dip and river regime are key hydrological parameters. According to them, one can get an idea of the water content, the nature and speed of the flow of a particular watercourse. What is the fall of the river? How to correctly calculate its slope? What determines the regime of a particular river? We will consider the answers to all these questions in our article. Last modified: 2025-01-23 12:01

Which is harder, granite or marble, nickel or aluminum? And what is hardness anyway? We will try to answer these questions in our article. A number of foreign scientists de alt with the problem of determining the hardness of minerals and substances. Among them are Albert Schor, Friedrich Moos, Johan August Brinell, William Vickers and others. However, the only and generally accepted method for calculating hardness in science still does not exist. Last modified: 2025-06-01 07:06

Geographic coordinates - latitude and longitude - are determined by the intersection point of two imaginary lines - the parallel and the meridian. The longest parallel from which latitude begins is the equator. Last modified: 2025-01-23 12:01

Newton's second law is perhaps the most famous of the three laws of classical mechanics that an English scientist postulated in the middle of the 17th century. Indeed, when solving problems in physics for the movement and balance of bodies, everyone knows what the product of mass and acceleration means. Let us consider in more detail the features of this law in this article. Last modified: 2025-01-23 12:01

How does an atom work? What is called the core? What is the electron shell? What were the building patterns?. Last modified: 2025-01-23 12:01

In physics, the concept of "heat" is associated with the transfer of thermal energy between different bodies. Due to these processes, heating and cooling of bodies, as well as a change in their states of aggregation, occurs. Let's take a closer look at what heat is. Last modified: 2025-01-23 12:01

Caucasus is a beautiful geographical area, located mainly on the territory of the majestic mountains of Eurasia. This region is located closer to the southern edge of the East European Plain, at the turn of Europe and Asia, and it is washed by the waters of the Black Sea on the western side and the Caspian Sea on the eastern side. Last modified: 2025-01-23 12:01

Centner is a measure of weight. How to convert centners to kilograms, and kilograms to centners. An article on how to easily translate weight: gram, centner, ton, kilogram. Last modified: 2025-06-01 07:06

In the plant world, the most perfect and numerous group is the department of angiosperms or flowering plants. These include all plants that are equipped with an organ of seed reproduction - a flower. In total, there are more than 350 thousand different plant species on the planet, and of these, ¾ of them belong to angiosperms. They can easily grow in water, arid deserts and cover the lands of the steppes with a multi-colored carpet. Last modified: 2025-01-23 12:01

Since many people have problems with writing essays during school time, this, of course, needs help. The article helps to understand the nuances of writing essays. Last modified: 2025-06-01 07:06

The article talks about what a national park is. Why they are created, how they differ from reserves and what are reserves. Last modified: 2025-01-23 12:01

Breakthrough is a word we hear a lot with the adjectives "scientific" and "technological". But there are other breakthroughs in life - pipes or batteries. We will not exclude one or the other, we will tell about all the meanings of the word. Last modified: 2025-01-23 12:01

Chemistry around us is much more than the average citizen can imagine. Without doing science professionally, we still have to deal with it in our daily lives. Everything that is on our table consists of chemical elements. Even the human body is made up of dozens of chemicals. Last modified: 2025-01-23 12:01

Becky Thatcher is one of the minor characters in the novel "The Adventures of Tom Sawyer" by Mark Twain. In the book, several key moments are connected with the girl, which vividly show her personality. In this article you can find all the information about the heroine and its brief description. Last modified: 2025-01-23 12:01

The indigenous population of Abkhazia came from the ancient peoples of the Western Caucasus. In the Assyrian inscriptions of the times of King Tiglathpalasar, they were mentioned as Abeshla, in ancient sources these are the tribes of the Abazgs and Apsils. Last modified: 2025-01-23 12:01

Area is an area on the surface of the earth or water, which is occupied by a particular species of plants, animals, fish. There is even a science that studies the patterns of appearance, development, existence of areas - areology. Man's influence on his own planet is such that we can deliberately or accidentally move, destroy, and sometimes create an area for a certain type of creatures. Last modified: 2025-01-23 12:01

Tact - what is it? When we talk about her, we tend to imagine a polite person who treats others with respect. But in fact, there is a difference between politeness and tact, what is it? To answer this question, we will give information about the latter in more detail. Last modified: 2025-01-23 12:01