Hydrochloric acid + calcium carbonate

Which is the layer underground where all empty spaces are filled with a combination of air and water ?

This element exists in adundance in the sun.explain how you would go about capturing sunlight.would this captured sunlight contain any of the element?

You are making a solution of calcium chloride dissolved in water. you add solid, stir, and it dissolves. you add just a spatula tip full, stir, and the solid does not dissolve. how could you describe the solutions before and after adding the spatula tip amount