What is the difference between technetium-99m and technetium-99?
Technetium-99m is a metastable nuclear isomer of technetium-99. Technetium-99m is commonly used in medical imaging due to its short half-life and ability to emit gamma rays, while technetium-99 is a radioactive isotope with a longer half-life that is used for various medical and industrial applications, such as in radiopharmaceuticals and nuclear medicine.