How do i know a molecule is polar or nonpolar? like amnoacids threonine and alanine?

⭐《ANSWER》

↪To know that a molecule is polar or non-polar

↪we will look that , does it contain the Electronegative elements that can create a partial positive or Negative charge, such as the HALOGENS

↪after this , also we can observe that , is there any amonia group or a carboxylic group that can create a positive or negative charge by transfer or acceptance of the Hydrogen atom

↪Also in case of the amino acids when the, acids are mixed in soluble solvent there is charge transfer , due to which there is formation of

〽ZWITTER ION