11 grade chemistry others
What is the atomic number of helium?
What is the atomic number of helium?
1 Answer
Askiitians Tutor Team
The atomic number of helium is 2.
Explanation: The atomic number of an element is the number of protons in the nucleus of its atoms. For helium, this number is 2. Since the atomic number also determines the element's position in the periodic table and its chemical properties, helium is placed in Group 18 (the noble gases) and Period 1.
Helium has two protons and, in its most common isotope, also two neutrons, making its atomic mass about 4 atomic mass units.
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