23) We know the law of Conservation of Mass states that mass is neither
created nor destroyed by chemical reactions or physical transformations so why
is the mass of a rusted nail greater than the mass of the original nail (assume
that all of the rust is attached to the nail).

Which best describes the present-day universe? opaque, expanding very slowly, stars produce heavy elements transparent, expanding at an accelerated rate, stars produce heavy elements opaque, expanding at an accelerated rate, stars produce only hydrogen and helium transparent, expanding very slowly, stars produce only hydrogen and helium