Most glass is made from a molecule called Silica.
Glass is mostly made of silica (SiO2). Silica is molecule, not an element, but in that case the most abundant element is oxygen, being that there are 2 oxygen atoms (O) to every 1 silicon atom (Si).
Glass is a homogeneous mixture.
Hydrogen. It is also the lightest element and the first element that ever formed.
The most common element in the universe is hydrogen.
That would be silicon, or SiO2
The most abundant element in the universe is hydrogen.
Ionic compounds are usually formed between a metal element and a non metal element in most cases. There are some exceptions such as ammonium nitrate though.
The key element in cement and glass is silicon.
Oxygen is the most abundant element in the Earth crust; I don't understand your term "formed".
silicon.
Obsidian is neither an element nor a compound. It is a naturally occurring volcanic glass formed when lava cools rapidly without crystal growth.
The element that is used to make pink glass is selenium. This element is also used to make glass that is red in coloring.