Why is Glass Transparent?

First, let’s start by pointing out that it’s not unheard of for materials to have different levels of opacity in different states. Water is transparent in liquid form, yet harder to see through when it is in the form of ice or vapor (though if it is diffuse enough, gaseous water is also no hindrance to our vision). This is because the opacity of any given material is a function of its structure and the energy level of the photons attempting to pass through it.

When photons with energy levels in the visible light range of the electromagnetic spectrum come into contact with an object, the electrons in that object typically absorb their energy and reflect some of it back in the form of colored light. But with transparent objects, those electrons are unable to absorb that energy. This is because glass is an amorphous solid, which means that the atoms making it up are not arranged in any sort of orderly pattern despite being more or less stable with regard to their position.

This disorderly structure makes it so that the electrons in glass cannot efficiently absorb the energy of photons that come into contact with it. But since that energy is not absorbed, the photons just continue on through to the other side (allowing us to see through the object). More orderly structures (with the exception of some crystalline patterns) make it harder for photons to pass through unaffected, which is why only higher energy photons (like X-rays) are able to penetrate opaque objects.

It’s actually an awesome question, and @JeSuisRickSpringfield hit upon the answer. It is important to know, however, that glass isn’t entirely transparent. It’s just transparent to visible light. It’s transparent for the same reason that x-rays go through parts of you without difficulty.

https://physics.stackexchange.com/questions/7437/why-is-glass-transparent

I never knew I needed an answer for this, but now I do.
Thank you @JeSuisRickSpringfield and @Caravanfan

Good explanations. One thing to add. Glass is in an intermediate state between solid and liquid

When I was in scool we were taught that glass is a colloidal suspension.

@LostInParadise I think that’s what @JeSuisRickSpringfield meant by amorphous solid.

It is because of arrangements of silicone atoms in a pattern