Why do all atoms of an element have the same atomic number, although they may have different mass numbers? . what do we call atoms of the same element with different mass numbers?

Determine the empirical formula of a compound containing 40.6 grams of carbon, 5.1 grams of hydrogen, and 54.2 grams of oxygen. in an experiment, the molar mass of the compound was determined to be 118.084 g/mol. what is the molecular formula of the compound? for both questions, show your work or explain how you determined the formulas by giving specific values used in calculations.

Quiz1. which physical state of nitrogen has the highest entropy? a solid© b gasoc liquid

Iwould appreciate if someone could me.