Why do molecules such as methane and water have a particular shape?
Methane is not 90 degrees from each other because it is not a 2-D structure; it is a 3-D structure. The hydrogens want to be as far away as possible from each other, and the most optimized way for them to do this is to form a tetrahedral structure, with an angle of 105.9 degrees. Water, I forgot. I think it had to do something with oxygen having 2 electron pairs that are “invisible”, but can repel the hydrogens. This pushes the hydrogen up.
