객관식Which of the following is the correct symbol for the isotope of potassium with 22 neutrons?103views
객관식What can be inferred about the age of a rock that contains equal amounts of potassium-40 and argon-40?115views
객관식A sample of chlorine contains two naturally occurring isotopes: chlorine-35 (mass = 34.969 u, abundance = 75.78%) and chlorine-37 (mass = 36.966 u, abundance = 24.22%). What is the average atomic mass of chlorine?111views
객관식If the mass of Br-81 is 80.9163 amu, which of the following is closest to the mass of Br-79?100views
객관식An atom of the isotope ¹³C contains how many protons (p), neutrons (n), and electrons (e)?110views