Figure out the weight of the glass by first figuring out the area of the sides.
There are four sides. Each side is a triangle with height 2ft and base 2ft. So the area of one of the triangles is 2 ft^2.
There are four sides, so there is a total of 8 ft^2. Each ft^2 weighs 2.45 pounds, for a total of 8*2.45 = 19.6 pounds
Since the chain can support up to 35 pounds, then the chain can support the light cover easily.