Elements

What is an Element?

An Element is a pure substance that cannot be broken down into simpler substances by chemical reactions.

• Building Blocks: Everything in the universe is made of elements.
• Atoms: The smallest particle of an element is an Atom.

Molecules of Elements

Atoms of some elements cannot exist alone. They combine with each other to form Molecules.

• Hydrogen ($H_2$): 2 Hydrogen atoms.
• Oxygen ($O_2$): 2 Oxygen atoms.

Classification of Elements

There are 118 known elements. They are broadly classified as:

1. Metals:
   • Shiny, malleable, ductile, good conductors.
   • Examples: Gold, Silver, Iron, Copper, Mercury (Liquid).
2. Non-Metals:
   • Dull, brittle, poor conductors.
   • Examples: Carbon, Sulfur, Oxygen, Hydrogen, Bromine (Liquid).
3. Metalloids:
   • Properties in between metals and non-metals.
   • Examples: Silicon, Boron.