When a molecule is said to be polar , it means the electrons are not shared evenly, so one end of the molecule is slightly negative and the other end is slightly positive.

Core idea (in plain language)

  • Different atoms pull on shared electrons with different strengths (this is called electronegativity).
  • If one side of a molecule pulls electrons more strongly, that side gains a partial negative charge (δ−), and the opposite side becomes partial positive (δ+).
  • This separation of charge creates a tiny “electric arrow” through the molecule called a dipole moment.

A classic example is water, H₂O: the oxygen end is slightly negative and the hydrogen end is slightly positive, so water is a polar molecule.

What “polar” implies

  • The molecule has an uneven distribution of electron density (charge is lopsided).
  • There is a partial positive end and a partial negative end (like a small bar magnet with two poles).
  • The molecule’s shape is usually not perfectly symmetrical, so the individual bond dipoles do not cancel out.

By contrast, a nonpolar molecule either shares electrons equally or has a symmetric shape that makes all the little dipoles cancel, giving no overall polarity.

One-sentence summary: A polar molecule is one with an uneven charge distribution, giving it a partially positive side and a partially negative side, and therefore an overall dipole moment.

Information gathered from public forums or data available on the internet and portrayed here.