An atom of an element that has the same number of protons but a different number of neutrons is called a(n): ion nucleus isotope mixture

50 pts plz what is the physical state of matter of baking soda.

What is the molar mass of a gas that has density of 2.054 g/l

Select all of the statements which are true. electrons are located in shells or orbits around the atom. electrons orbit slowly around the atom. electrons travel in one flat path around the nucleus of an atom. the valence of an atom is determined by the number of electrons in the atom's outermost shell.