Why are snowflakes hexagonal?

Snowflakes are hexagonal because water freezes into hexagonal shapes. But why? In this video Wilf talks about why H2O molecules are polar and why this results in hexagonal structures for ice. He also shows how to make a paper snowflake and has some thoughts to share about his christmas jumper. Wilf Wonders made this video for Santa Loves STEM with the Institute for Engineering Technology (IET). #SantaLovesSTEM - find out more and download teacher guides here: https://education.theiet.org/secondary/teaching-resources/science-of-snowflakes/ CREDITS --------------- Snowflakes: https://upload.wikimedia.org/wikipedia/commons/c/c2/SnowflakesWilsonBentley.jpg Plate XIX of "Studies among the Snow Crystals ... " by Wilson Bentley, "The Snowflake Man." From Annual Summary of the "Monthly Weather Review" for 1902. Stellate snowflake photographed Vermont 2015. https://en.wikipedia.org/wiki/File:Snowflake_Detail.jpg Freshly fallen snowflakes photo by Thomas Bresson from Belfort, France https://en.wikipedia.org/wiki/File:ComputerHotline_-_Snow_crystals_(by).jpg Ice lattice structure image by Psiĥedelisto, based on version by Dbuckingham42 https://en.wikipedia.org/wiki/File:Ice_Ih_Crystal_Lattice.png Jingle Bells (Calm) by Kevin MacLeod Link: https://incompetech.filmmusic.io/song/3943-jingle-bells-calm- License: https://filmmusic.io/standard-license Jingle Bells by Kevin MacLeod Link: https://incompetech.filmmusic.io/song/3942-jingle-bells License: https://filmmusic.io/standard-license