Why are lenses made from amorphous solids?

Because amorphous solids are not crystalline and do not distort light.

Explanation:

Amorphous solids are that solids in which  atoms and molecules are not organised in definite pattern.

Amorphous solids have not ordered  internal structure but crystalline solids will have internal planes .In crystalline solids ,internal reflection and refraction can occur.Thus, distorting the light when  passing through the crystalline solids.In amorphous, solids have no ordered internal structure therefore, there are no refraction or reflection and hence , no distortion of light.

That is why lenses are made from amorphous solids.

answer:

the reaction is type of combination reaction.

explanation:

on the product side, there are 2 molecules of bonded to fe   which means one atom of fe are combined two molecules of . so, balanced chemical equation becomes :

this reaction follows the reaction type of combination reaction. a combination reaction is defined as chemical reaction in which reactants combines together to form a single product.

a. energy is absorbed in the reaction.

if in a given reaction the energy of products is greater than the energy of reactants it means that reaction is endothermic and during the reaction, the energy is absorbed by reactants. in an endothermic reaction, the products have more stored chemical energy than the reactants. and in this reaction the reactants are more stable than products before the compounds with less energy are always more stable.