Name an element that exists in a crystal lattice at stp

As a part of an experiment a student burns propane to produce carbon dioxide and water she remembers that she must follow the law conservation of matter when writing a balanced chemical equation which of these equation adheres to the law of conservation of matter

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?

Nonmetal halogen family atmoic mass 35