Select all of the particle diagrams that represent a pure substance

what is the density of an object that has a mass of 10 g and a volumeof 5 ml? a. 0.5 g/ mlb. 2 g/mlc. 15 g/ mld. 50 g/ ml

Plz choose one of the compounds from the table and explain how you know the numbers of atoms in your formula. is it possible for two different compounds to be made from the exact same two elements? why or why not? with a limited number of elements (less than 120 are known), does this mean we also have a small number of compounds or do we have a large number of compounds in this world?

Great amounts of electromagnetic energy from our sun and other bodies in space travel through space. which is a logical conclusion about these electromagnetic waves? their energy must be very their frequency must be very low these waves can travel without a medium they only travel through a vacuum of space