Is it correct that a hydrogen atom only has 1 electron and 1 proton since the atomic mass is 1? Also, is the hydrogen ion composed of a single proton and no electrons?

In an ionization process we know that sometimes a hydrogen ion or H+ is taken out of a compound to be transferred to water, in what we know as an acid-base reaction. For example if we have HCl, which is attracted to water, the bond between the hydrogen and chlorine would be broken and the electron pair between them would have all gone to the Cl. Hence making the chlorine having a negative charge and the hydrogen a positive charge.

Does this hydrogen only have 1 proton making it an ion?

  • $\begingroup$ So, yes. A Hydrogen atom without an electron is a proton, and it is an ion, a positive ion. $\endgroup$ – Maurice Sep 23 '20 at 8:58

A single hydrogen atom is just one proton and one electron. However, just to make clear, elemental hydrogen exists as $\ce{H2}$, which is a gas.

The atomic number gives the number of protons. The atomic mass is, approximately, the number of protons and neutrons.

When a hydrogen atom loses an electron, then it becomes the hydrogen ion ($\ce{H+}$) which is just a single proton.

As for dissolving HCl in water, we known that hydrogen and chlorine are bound covalently in the gas phase, however, dissolving in water causes the electrons to be totally given up by hydrogen to chlorine. This leaves us with an $\ce{H+}$ and $\ce{Cl-}$.

Let me mention, though, that in aqueous solutions, that $\ce{H+}$ will form a hydronium ion with water, giving $\ce{H3O+}$.


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