Question

I will mark the first answerer as brainlist
Long notes on
STRUCTURE OF MATTER
Like
Elements
Compounds
Mixtures
Symbol
Formula of this topic
Valency (define and explain)
Chemical equations
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Answer 1

Structure of matter

a substance made up of atoms of two or more different elements joined by chemical bonds. a group of atoms that are held together by chemical forces. It is the smallest unit of matter that can exist by itself and keep all of a substance's chemical properties.

elements

Microscopic view of the molecules of the element nitrogen (gas phase). Note that an element: consists of only one kind of atom, cannot be broken down into a simpler type of matter by either physical or chemical means.

compounds

pure substance composed of two or more different elements joined by chemical bonds

Mixtures –a combination of two or more pure substances that are not chemically combined. physical forces, not chemical

some symbols

Z Symbol Element Group Period

1 H Hydrogen 1 1

2 He Helium. 18 1

3 Li Lithium 1 2

formula: The structural formula of propane. This representation is called a structural formula, in which lines depict two electron bonds between atoms. Look at the propane structure and observe that the four bonds to each carbon complete its valence orbitals with eight electrons. ... This representation is a molecular formula

valency:

The valency of an element is the number of hydrogen atoms that can combine with or replace (either directly or indirectly) one atom of the element. In other words, the valency of an element is the number of electrons an atom of the element uses to combine with atoms of other elements - it is the combining power of an atom of the element. In an atom, the valence electrons are the electrons that can be used in combining with other atoms - these are the electrons in the orbitals of the outermost shell (also called valence shell).

chemical equations:

A balanced chemical equation can provide the following information : The reactants and products through their symbols and formulae. The ratio of molecules of reactants and products. As molecular masses are expressed in unified mass (u), the relative masses of reactants and products are known from the equation