Domanda apertaWhich of these refers to atoms with the same atomic number but different atomic masses?1936views
Domanda apertaThe atomic number of fluorine is 9 and its atomic mass is 19. How many neutrons does fluorine have?1742views
Domanda apertaOne isotope of sodium has 11 protons and 7 neutrons. What is the mass number of this isotope?1900views