how come glass is transperant while all ingredients used to make it are opaque?

Answer 1

Glass is made mainly from sand, and sand is mostly silicon dioxide, which IS transparent. It's just that in sand the silicon dioxide is broken into tiny grains, often with scratched and roughened surfaces. Multiple reflections from the grains and surface scratches stop the light getting through.

The real question is: why is silicon dioxide transparent? And the basic answer is: because it is a very good insulator. This means that the electric field of an incident electromagnetic wave is not reduced to zero, as it would be in a conductor. So the light carries on as if nothing had happened (well, not quite: it slows down to about 2/3 its speed in air, which is why you get the reflections mentioned above) and we see the material as transparent.

Answer 2

The main ingredient in glass is sand, which only appears to be opaque because it is broken into small particles with many reflective surfaces. It can be said that sand is finely ground or shattered glass.

Answer 3

If you see the structure of glass , the constituent particles are far off , hence there is much space between them which accounts for the transparency of glass.