Atoms and Particles of Matter

Dear Kalpita.

It's been awhile since I've last posted. Oh well. We're moving on. but of course I mist Review as usual:

Matter is anything made of atoms and molecules, Matter is classified as an element, a compound, or a mixture

Element: a substance made out of one type on atom
Compound: Two or more elements. Can only be seperated trough a chemical reaction
Mixture: A mix of two substances that can be seperated easily

Chemistry:the science of the properties, composition and changes in matter

Physical Change: Changes the appearance of the substance.
example: Water freeezing


Chemical Change: the substance becomes a different substance:
Example: rust

Weight:The measurment of the force of gravity on an object

Mass:how much matter an object contains

Volume: Hiw much space an object takes up

Density: how much mass per unit of volume

Now For The New Stuff

Apparently I need to intorduce Democritus

Democritus was an ancient Greek Philosopher. He formulated an atomic theory for the cosmos. He was liked by Aristotle and hated by Plato. He and is mentor Leuicippus believed that everything was made of atoms, that atoms were physically indivisible, that they were indestructible, that they were constantly moving and that empty space lay between all atoms.

As you can see some of these ideas were right and many were wrong but he basically had the right idea. This is why Democritus is believed the be the "father of modern science".

Democritus originally named atoms Atomos, which means "uncuttable" but which has also taking on the meaning of "smallest indivisible particle of matter."

An atom is the smallest particle of an element


Next up we have

John Dalton

John Dalton was many things. He was an English man that dipped into many sciences, including meteorology, chemistry and physical science. He was best known for researching atomic theory and color blindness.

Here is what John Dalton believed about atoms


The atoms of different elements can be distinguished by their atomic weight

All atoms of the same element are identical

Atoms of one element can a bond with the atoms of another atoms to form a chemical compound, a compound that has the same number of types of atoms

Atoms can't be created, divided into smaller particles or destroyed in a chemical reaction.



Scientists have found exceptions to many of his "rules" but his theory has helped form the basis of our understanding of atoms.

An atom can be seen through an electron microscope.

A chemical bond is the attraction between molecules or atoms that creates a chemical compound.


A molecule is a combination of two or more atoms that are bonded together.



That's enough for today. Tomorrow we may or may not talk about the composition of atoms