In the absence of this element, the plant does not grow tall, the ripening of fruits is inhibited. Atomic number 15. Indicate the name, symbol, relative atomic mass, valency of the element.

D.Mendeleev predicted properties of several metals even before they were discovered. For example:

This is an Italian scientist. He is best known for his contributions to molecular theory. The number of elementary particles (atoms, molecules, ions or other particles) in 1 mole of a substance, equal to 6.02 × 10 23, is known as a constant

In what year was the Periodic table formulated?

Gives a red color to the blood in the body, is part of hemoglobin. Atomic number 26. Indicate the name, symbol, relative atomic mass, valency of the element

This sea is also called salt sea. It contains about 30-35 kinds of minerals like potassium, magnesium, sodium, bromine, iodine, chlorine, etc. The high mineral and salt content of the waters make it impossible for fish or plants to live.

Was a Russian chemist who became a professor at Saint Petersburg University. He is best known for identifying properties of elements and the creation of the Periodic Table of elements, which is still used today.

One of the allotropic forms of carbon: -the hardest substance in nature, nonconducter, used as an abrasive, transparent

Gases have a certain volume. Yes or no?

Who was the Swedish scientist, Nobel Prize laureate (1903), who proposed the basic principles of the theory of electrolytic dissociation in 1887?

Who discovered one of the most important chemical elements - oxygen?

The northern orchid grows in soil rich in this element. The relative atomic mass is 40. Indicate the name, symbol, atomic number, and valency of the element.