Molecules can be divided into two main types: polar and nonpolar. They act differently because of something called electronegativity. This is just a fancy way of saying how good an atom is at pulling in electrons when it forms a bond with another atom.

Polar Molecules

• Examples: Water (H₂O), Ammonia (NH₃)
• What They Are Like: In polar molecules, the atoms have different electronegativities. For example, in water, oxygen pulls on electrons harder than hydrogen does. This causes parts of the molecule to have small electrical charges. Because of this, polar molecules are attracted to each other and can mix well with other polar substances.

Nonpolar Molecules

• Examples: Oil, Hexane (C₆H₁₄)
• What They Are Like: Nonpolar molecules have atoms that share electrons more equally. This means the charges are balanced out. Because of this, nonpolar molecules don’t mix well with polar ones. A common example of this is oil floating on water.

Understanding how these two types of molecules interact is really important in chemistry. It helps us figure out things like how well substances can mix together and how they behave in different situations!