Elements, Mixtures and Compounds

What is an Element?

Element is a pure substance that cannot be broken down further into two or more simpler substances by chemical processes or by electricity. Elements can be classified into metals, non-metals and metalloids based on their properties. Each element has a unique symbol consisting of one or two letters. Elements are made up of atoms. 

What are Atoms?

Atoms are the smallest properties of an element that have the properties of the chemical. 

What is a molecule?

A molecule is a group of two or more atoms that are chemically combined. Metals exist as large numbers of atoms arranged in a giant structure. Most non-metals exist as molecules.

What is a Compound?

A compound is a pure substance that contains two or more elements chemically combined. A compound is made up of different elements chemically combined in a fixed ratio. The smallest particle of a compound is a molecule. Heat can be used to form compounds and break down compounds unto elements or simpler compounds. Such a reaction is called thermal decomposition. Compounds can also be broken down into simpler substances by using electricity. 

What are Mixtures?

Mixtures are formed when two substances are added together without chemical bonds being formed. An alloy is a mixture of a metal with other elements.

Periodic Table

The periodic table is a table of the chemical elements, showing the symbols for the elements, their full names, their atomic numbers and their mass number. It organizes them into groups and periods (columns and rows) based on their structure and properties. It is called "the periodic table" because the horizontal rows are named "periods."