What is the name of the compound Si₉Br₃?

Which of the following is true about the speed of light? it depends on the wavelength.

Witch two conditions can limit the usefulness of the kinetic molecular theory in describing gas behavior?

Which factor is likely to impact the possible number of compounds? presence of unlimited number of elements in the periodic table the inability of atoms to align perfectly with other atoms the ability of all elements to react with every other element all elements being equally reactive