Descripcion de la materia
Matter is anything that has mass and takes up space. All the “stuff” around is matter.
Chemistry is the study of matter, the properties of matter and how matter changes.Substance is a single kind of matter that is pure and has a specific set of properties.
For example:
Two students have a different set of characteristics that makes one totally different fromthe other.
When we talk about a SET of PROPERTIES, we covered all the characteristics that substance has. Substances may share some characteristics, but there is no substance with the exactsame set of properties of another substance.
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Matter can be classified in to two broad categories: pure substances and mixtures.
A moleculeis a combination of 1 or two elements or types of atoms forming a chemical bond (a force of attraction between atoms).
* The difference between molecules and compounds is basically thenumber of elements they have.
* Another important difference is the type of chemical bond.
When elements are chemically combined they form compounds having properties that are different fromthose of the uncombined elements.
Example:
H2O (water) have properties that are different from the ones of the hydrogen and oxygen that forms it.
Atoms: Atoms are the basic buildingblocks of matter that make up everyday objects.
They are the smallest piece of matter you can have that chemists can do reactions with.
Each element has it's own type of atom.
Atoms are madeout of three basic particles:
The forces of attraction between the electrons and the protons hold an atom together.
MIXTURE
* Is a combination of two or more substances that are notchemically combined.
* The composition of a mixture is variable.
* Its components are easily separated.
Each of the substances in a mixture keeps the original chemical properties!!
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