Dyes for fabrics

Published April 14, 2018

Dyes for fabrics

In 1856, the English chemist William Perkin persevered in experiments to obtain quinine, but instead he discovered one of the first artificial colors, Mowein. From this time, artificial colors for the fabric originate. Until then, people used only natural dyes for tissue. Kampeshevo wood and roots of the madder...

Inks for writing

Published April 14, 2018

Inks for writing

You will not believe it, but all the well-known ink for the letter will be obtained if you take a little oak, alder and ash tree bark, boil them in water, add berries of hardness, and then throw a piece of iron and pour the soup porridge and a mug of kvass honey! It was such ink for writing on "acidic schachas" - they were called "cooked" yet - used...

Electrons in a hydrogen molecule

Published April 14, 2018

Electrons in a hydrogen molecule

Have you ever thought of what forces hold a molecule of matter from decay into atoms? Today it is known that these forces are called chemical, and they are of an electromagnetic nature. In general, the chemical bond can be explained as the result of the collectivization of external - valence electrons of the connecting atoms. At certain distances between the nuclei, collectivized, for example, electrons in the hydrogen molecule...

Laws of Svante Arrhenius

Published April 14, 2018

Laws of Svante Arrhenius

Ever since school, everyone knows that the rate of chemical reactions increases with increasing temperature and, conversely, the lower the temperature, the lower the reaction rate. These laws of Svante Arrhenius were introduced to the rank of fundamental in 1889 and laid the foundations of one of the most important branches of chemistry...

The content of vitamin C

Published April 14, 2018

The content of vitamin C

Autumn is inseparably linked with the processes of harvesting, fruits and vegetables, nutrition that enriches the body with various vitamins, especially vitamin C. Probably everyone is interested to know what vitamin C content in freshly picked fruits and in those fruits that were stored for a week, a month, half a year, as the harvest of the last year to spring loses a significant...

Lead tree

Published April 14, 2018

Lead tree

Demonstration of the laws of electrolysis, described by M. Faraday, can be done with the help of a very interesting experience "growing" a lead tree or as it is called a Saturn tree. Such a name for the obtained plumbum crystals came to us from the time of the alchemists - they called the saturn of Saturn. But first things first...

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