교과서 질문Fluorine occurs naturally as a single isotope. How many protons, neutrons, and electrons are present in deuterium fluoride (2HF)? (Deuterium is 2H.)1068views
미해결 질문Which of these refers to atoms with the same atomic number but different atomic masses?1773views
미해결 질문One isotope of sodium has 11 protons and 7 neutrons. What is the mass number of this isotope?1758views