Free radical

Free radical or radical the name of particles in chemistry. Free radicals can be gaseous, liquid, and solid.

These atoms and molecules have a short lifespan.

Free radicals enter into chemical reactions with metals.

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Isotope.

Isotope (Ισότοπο) means isos (ἴσος) "equal" and topos (τόπος) "place". These are varieties of the same chemical element.

Isotopes have the same atomic number, but they have different mass numbers.

These elements are studied in chemistry.

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Iodine.

Iodine is a chemical element. Its symbol is I. This element has its own isotopes.

Iodine can be black or purple in color. Also, it has a smell.

This mineral is found in some foods.

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Chemistry.

Chemistry is one of the most important and interesting school subjects. This science has similar parts with physics. There are many formulas and tables.

H₂O is a formula of water. Students can conduct experiments in special rooms during lessons. 

Chemical elements everywhere. Foods, furniture, our body; all of them have chemical elements.

This science may be difficult for someone. Thanks to chemestry we know about salt, sugar, and fats. It is necessary to know in life.

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