3. What liquid is secreted into the mouth and performs chemical digestion?

Saliva, which contains assorted enzymes that begin digestion; an example is amylase, which begins digestion of carbohydrates by digestion into simpler sugars

Explanation:

answer is: naturally occurring solid, inorganic compound or element is mineral.

minerals usually have crystalline form, that means than crystal constituents (atoms, molecules or ions) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions.

for example magnetite is a mineral of iron oxide (fe₂o₃).

calcite is a carbonate mineral and the most stable polymorph of calcium carbonate (caco₃).

dolomite is an   carbonate mineral composed of calcium magnesium carbonate (camg(co₃)₂).