Which of the following element does not contain any neutron?

Option 4 : Hydrogen

The correct answer is Hydrogen.

Explanation:

• Helium, Boron, and Beryllium are the elements from the modern periodic table having an atomic number 2, 5, and 4 respectively.
• It has different properties which are used according to their metallic and non-metallic nature. 

Some points to know about Neutrons:  

1. It was discovered by James Chadwick in 1932. He was a British Physicist.
2. It has zero charges and 1.674*10^-27 kg or 1.00867 unit mass.
3. It is present inside the nucleus in the atom.
4. Hydrogen is the only element in which neutron does not present.
5. Electromagnetic force bind electrons with the nucleus.
6. Atoms having the same number of electrons and protons are neutral.
7. If electrons are less than the proton, the atom carries a positive charge and if the electrons are more than the proton, the atom carries a negative charge.