What is the atomic number of Lawrencium, a chemical element that is classified as the
last member of the actinides?
Show answer & explanation
Correct answer: B
Explanation
The correct answer is Option 2 i.e. 103.
Lawrencium (Lr) is a synthetic chemical element with the atomic number 103. It holds the distinction of being the last member of the actinide series, a group of 15 metallic, radioactive elements on the periodic table. As a synthetic element, it is not found naturally and must be created in a laboratory, primarily for scientific research purposes. Its most stable isotope, Lawrencium-262, has a half-life of about 3.6 hours.