Which of the following elements of the periodic table has atomic number 1?
Answer & explanation
Correct answer: option 1
The correct answer is option 1. Hydrogen.
The element with atomic number 1 is Hydrogen
The atomic number of an element is equal to the number of protons in the nucleus of an atom. In the periodic table, elements are arranged by increasing atomic number, so the element with the number 1 is hydrogen (H).