A student was given the volume and description of a substance and was asked to determine its density. What information is missing?

What is the percent by mass of oxygen in fe2o3

An atomic nucleus is composed ofa)protons. b)protons and neutrons. c)protons and electrons. d)protons, neutrons, and electrons.

Which is a characteristic of the electron sea model for metallic bonding? molecular orbitals overlap to produce bands. electrons flow easily between metal nuclei. electrons are in fixed positions in the orbitals. atomic nuclei are arranged in an irregular pattern.