[Indranil (OP)]

What is the proton number of N in NH3? the answer is 7 because the proton number does not change. But what is the proton number of N in NH4+? still 7 or 8? I am confused.

[Bored chemist]

What does the "textbook" say?

[Kryptid]

Like I said in another of your threads, the number of protons in a given element never changes. Nitrogen always has 7 protons, regardless of what molecule it is in or what its electric charge is. The number of protons is what defines the element. If the number of protons was different, it would no longer be nitrogen.

[Indranil (OP)]

Like I said in another of your threads, the number of protons in a given element never changes. Nitrogen always has 7 protons, regardless of what molecule it is in or what its electric charge is. The number of protons is what defines the element. If the number of protons was different, it would no longer be nitrogen.

I also agree with you but I am confused about why N got positivie charge on it. As I know positive charge means proton. one positive charge means one extra proton. could you explain it, please?

[chiralSPO]

Like I said in another of your threads, the number of protons in a given element never changes. Nitrogen always has 7 protons, regardless of what molecule it is in or what its electric charge is. The number of protons is what defines the element. If the number of protons was different, it would no longer be nitrogen.

I also agree with you but I am confused about why N got positivie charge on it. As I know positive charge means proton. one positive charge means one extra proton. could you explain it, please?

Yes, protons have positive charge. But, as has been pointed out many times, changing the number of protons in the nucleus changes the identity of the element. Instead, electrons are exchanged between atoms. Any atom (or molecule) with an equal number of protons and electrons in it will be neutral, any atom (or molecule) with more electrons than protons will be negatively charged (magnitude of charge scales linearly with the difference is), and any atom (or molecule) with fewer electrons than protons will be positively charged (again magnitude of charge scales linearly with the difference is.)

Note that it is also possible to add one or more protons to an atom (or molecule) without changing the element. each proton just has to be its own nucleus, ie a H⁺ ion. Chemists and biologists will often talk about the "protonation state" of a species, meaning how many of theoretically exchangeable protons are still on there.

[Indranil (OP)]

Like I said in another of your threads, the number of protons in a given element never changes. Nitrogen always has 7 protons, regardless of what molecule it is in or what its electric charge is. The number of protons is what defines the element. If the number of protons was different, it would no longer be nitrogen.

I also agree with you but I am confused about why N got positivie charge on it. As I know positive charge means proton. one positive charge means one extra proton. could you explain it, please?

Note that it is also possible to add one or more protons to an atom (or molecule) without changing the element. each proton just has to be its own nucleus, ie a H⁺ ion. Chemists and biologists will often talk about the "protonation state" of a species, meaning how many of theoretically exchangeable protons are still on there.

Could you explain this point in an easy way please 'each proton just has to be its own nucleus, ie a H⁺ ion.'?

[Kryptid]

Could you explain this point in an easy way please 'each proton just has to be its own nucleus, ie a H+ ion.'?

The atom is bonded to a positive hydrogen ion.

[chiralSPO]

If you add a proton to the actual nucleus of a chloride ion (which has 17 protons and 18 electrons), it becomes an argon atom (with 18 protons and 18 electrons). However, if you don't combine nuclei, and just "stick" the proton "in" the electron cloud of the chloride it forms a molecules of hydrogen chloride (which has 18 electrons surrounding a nucleus with 17 protons and a nucleus with 1 proton.)

Cl^– + H⁺ → HCl (chemical reaction)
Cl^– + H⁺ → Ar (nuclear reaction)

[Indranil (OP)]

Could you explain this point in an easy way please 'each proton just has to be its own nucleus, ie a H+ ion.'?

The atom is bonded to a positive hydrogen ion.

But why to a positive hydrogen ion, why not another positive ion? Could you explain it, please?

[Indranil (OP)]

If you add a proton to the actual nucleus of a chloride ion (which has 17 protons and 18 electrons), it becomes an argon atom (with 18 protons and 18 electrons). However, if you don't combine nuclei, and just "stick" the proton "in" the electron cloud of the chloride it forms a molecule of hydrogen chloride (which has 18 electrons surrounding a nucleus with 17 protons and a nucleus with 1 proton.)

Cl^– + H⁺ → HCl (chemical reaction)
Cl^– + H⁺ → Ar (nuclear reaction)

1. In HCl, you mentioned 18 electrons of Cl surrounding 17 protons but how many electrons surrounding 1 proton of H? 2 or 18?
2. But why to a positive hydrogen ion, why not another positive ion? Could you explain it, please?

[chiralSPO]

If you add a proton to the actual nucleus of a chloride ion (which has 17 protons and 18 electrons), it becomes an argon atom (with 18 protons and 18 electrons). However, if you don't combine nuclei, and just "stick" the proton "in" the electron cloud of the chloride it forms a molecule of hydrogen chloride (which has 18 electrons surrounding a nucleus with 17 protons and a nucleus with 1 proton.)

Cl^– + H⁺ → HCl (chemical reaction)
Cl^– + H⁺ → Ar (nuclear reaction)

1. In HCl, you mentioned 18 electrons of Cl surrounding 17 protons but how many electrons surrounding 1 proton of H? 2 or 18?
2. But why to a positive hydrogen ion, why not another positive ion? Could you explain it, please?

In HCl there is a total of 18 electrons around both the H nucleus and the Cl nucleus. Depending on how we do the accounting, we can say that both nuclei share all of the electrons, or that the 10 core electrons on Cl stay on Cl and the other 8 (valence electrons) are shared, or that the Cl has 16 electrons it can call its own, and 2 that are shared with the H, that the Cl has 17 electrons of its own, and H has 1, or that the Cl has all 18 electrons and thee H is just there... The important thing is that everyone agrees on the total number of particles.

I gave the example of positive hydrogen, because you had asked about protons. But ammonia (and other compounds with lone pairs) certainly will interact with other cations (like Li⁺)  in similar ways.